plpgsql - additional extra checks

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 6dc438a152..7de0b8005a 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -4862,7 +4862,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -4874,6 +4874,11 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
+   <para>
+    The setting <varname>plpgsql.extra_warnings</> to <literal>all</> is a 
+    good idea in developer or test environments.
+   </para>
+
  <para>
   These additional checks are enabled through the configuration variables
   <varname>plpgsql.extra_warnings</> for warnings and
@@ -4890,6 +4895,30 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
      </para>
     </listitem>
    </varlistentry>
+
+   <varlistentry>
+    <term><varname>strict_multi_assignment</varname></term>
+    <listitem>
+     <para>
+      Some <application>PL/PgSQL</> commands allows to assign a values to
+      more than one variable. The number of target variables should not be
+      equal to number of source values. Missing values are replaced by NULL
+      value, spare values are ignored. More times this situation signalize
+      some error.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><varname>too_many_rows</varname></term>
+    <listitem>
+     <para>
+      When result is assigned to a variable by <literal>INTO</literal> clause,
+      checks if query returns more than one row. In this case the assignment
+      is not deterministic usually - and it can be signal some issues in design.
+     </para>
+    </listitem>
+   </varlistentry>
   </variablelist>
 
   The following example shows the effect of <varname>plpgsql.extra_warnings</>
@@ -4909,6 +4938,34 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
+
+  The another example shows the effect of <varname>plpgsql.extra_warnings</>
+  set to <varname>strict_multi_assignment</>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of evaluated attributies (1) does not match expected attributies (2)
+WARNING:  Number of evaluated attributies (3) does not match expected attributies (2)
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
  </para>
  </sect2>
  </sect1>
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 9716697259..c14fdc0233 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3623,6 +3623,24 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	bool		too_many_rows_check;
+	int			too_many_rows_level;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+	{
+		too_many_rows_check = true;
+		too_many_rows_level = ERROR;
+	}
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+	{
+		too_many_rows_check = true;
+		too_many_rows_level = WARNING;
+	}
+	else
+	{
+		too_many_rows_check = false;
+		too_many_rows_level = NOTICE;
+	}
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3672,7 +3690,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_check)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -3792,7 +3810,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_check))
 			{
 				char	   *errdetail;
 
@@ -3801,7 +3819,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				ereport(too_many_rows_level == WARNING && !stmt->strict ? WARNING : ERROR,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
 						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
@@ -6027,12 +6045,48 @@ exec_move_row(PLpgSQL_execstate *estate,
 		int			t_natts;
 		int			fnum;
 		int			anum;
+		bool		strict_multiassignment_check;
+		int			strict_multiassignment_level;
+
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+		{
+			strict_multiassignment_check = true;
+			strict_multiassignment_level = ERROR;
+		}
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+		{
+			strict_multiassignment_check = true;
+			strict_multiassignment_level = WARNING;
+		}
+		else
+		{
+			strict_multiassignment_check = false;
+			strict_multiassignment_level = NOTICE;
+		}
 
 		if (HeapTupleIsValid(tup))
 			t_natts = HeapTupleHeaderGetNatts(tup->t_data);
 		else
 			t_natts = 0;
 
+		if (strict_multiassignment_check)
+		{
+			int		i;
+
+			anum = 0;
+			for (i = 0; i < td_natts; i++)
+				if (!TupleDescAttr(tupdesc, i)->attisdropped)
+					anum++;
+
+			if (anum != row->nfields)
+			{
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of evaluated attributies (%d) does not match expected attributies (%d)",
+									anum, row->nfields)));
+			}
+		}
+
 		anum = 0;
 		for (fnum = 0; fnum < row->nfields; fnum++)
 		{
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 1ebb7a7b5e..dceb710703 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index 2b19948562..18bff2a27e 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1024,7 +1024,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index 7d3e9225bb..17770c1cdc 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3422,6 +3422,54 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of evaluated attributies (1) does not match expected attributies (2)
+WARNING:  Number of evaluated attributies (3) does not match expected attributies (2)
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of evaluated attributies (1) does not match expected attributies (2)
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 6c9399696b..8d0b24ea93 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2840,6 +2840,57 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 7d23ed437e..efa48bc13c 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -4951,7 +4951,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -4963,6 +4963,11 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
+   <para>
+    The setting <varname>plpgsql.extra_warnings</varname> to <literal>all</literal> is a 
+    good idea in developer or test environments.
+   </para>
+
  <para>
   These additional checks are enabled through the configuration variables
   <varname>plpgsql.extra_warnings</varname> for warnings and
@@ -4979,6 +4984,30 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
      </para>
     </listitem>
    </varlistentry>
+
+   <varlistentry>
+    <term><varname>strict_multi_assignment</varname></term>
+    <listitem>
+     <para>
+      Some <application>PL/PgSQL</application> commands allows to assign a values to
+      more than one variable. The number of target variables should not be
+      equal to number of source values. Missing values are replaced by NULL
+      value, spare values are ignored. More times this situation signalize
+      some error.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><varname>too_many_rows</varname></term>
+    <listitem>
+     <para>
+      When result is assigned to a variable by <literal>INTO</literal> clause,
+      checks if query returns more than one row. In this case the assignment
+      is not deterministic usually - and it can be signal some issues in design.
+     </para>
+    </listitem>
+   </varlistentry>
   </variablelist>
 
   The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
@@ -4997,6 +5026,34 @@ WARNING:  variable "f1" shadows a previously defined variable
 LINE 3: f1 int;
         ^
 CREATE FUNCTION
+</programlisting>
+
+  The another example shows the effect of <varname>plpgsql.extra_warnings</varname>
+  set to <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of evaluated attributies (1) does not match expected attributies (2)
+WARNING:  Number of evaluated attributies (3) does not match expected attributies (2)
+ foo 
+-----
+ 
+(1 row)
 </programlisting>
  </para>
  </sect2>
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index ec480cb0ba..0879e84cd2 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3629,6 +3629,24 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	bool		too_many_rows_check;
+	int			too_many_rows_level;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+	{
+		too_many_rows_check = true;
+		too_many_rows_level = ERROR;
+	}
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+	{
+		too_many_rows_check = true;
+		too_many_rows_level = WARNING;
+	}
+	else
+	{
+		too_many_rows_check = false;
+		too_many_rows_level = NOTICE;
+	}
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3678,7 +3696,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_check)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -3798,7 +3816,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_check))
 			{
 				char	   *errdetail;
 
@@ -3807,7 +3825,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				ereport(too_many_rows_level == WARNING && !stmt->strict ? WARNING : ERROR,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
 						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
@@ -6033,12 +6051,48 @@ exec_move_row(PLpgSQL_execstate *estate,
 		int			t_natts;
 		int			fnum;
 		int			anum;
+		bool		strict_multiassignment_check;
+		int			strict_multiassignment_level;
+
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+		{
+			strict_multiassignment_check = true;
+			strict_multiassignment_level = ERROR;
+		}
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+		{
+			strict_multiassignment_check = true;
+			strict_multiassignment_level = WARNING;
+		}
+		else
+		{
+			strict_multiassignment_check = false;
+			strict_multiassignment_level = NOTICE;
+		}
 
 		if (HeapTupleIsValid(tup))
 			t_natts = HeapTupleHeaderGetNatts(tup->t_data);
 		else
 			t_natts = 0;
 
+		if (strict_multiassignment_check)
+		{
+			int		i;
+
+			anum = 0;
+			for (i = 0; i < td_natts; i++)
+				if (!TupleDescAttr(tupdesc, i)->attisdropped)
+					anum++;
+
+			if (anum != row->nfields)
+			{
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of evaluated attributies (%d) does not match expected attributies (%d)",
+									anum, row->nfields)));
+			}
+		}
+
 		anum = 0;
 		for (fnum = 0; fnum < row->nfields; fnum++)
 		{
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 1ebb7a7b5e..dceb710703 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index 2b19948562..18bff2a27e 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1024,7 +1024,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index d6e5bc3353..72776c2e2f 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3422,6 +3422,54 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of evaluated attributies (1) does not match expected attributies (2)
+WARNING:  Number of evaluated attributies (3) does not match expected attributies (2)
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of evaluated attributies (1) does not match expected attributies (2)
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 1c355132b7..189750316c 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2840,6 +2840,57 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 7d23ed437e..af1cf4ab95 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -4951,7 +4951,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -4963,26 +4963,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>all</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes only one:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as SELECT INTO.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use NULL for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a WARNING or
+        ERROR whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an INTO statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -4998,8 +5034,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index d096f242cd..2ce51213f1 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3559,6 +3559,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3597,9 +3603,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -3608,7 +3615,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level >= WARNING)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -3722,19 +3729,26 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level >= WARNING))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				errlevel = stmt->strict || stmt->mod_stmt ? ERROR : too_many_rows_level;
+				use_errhint = !(stmt->strict || stmt->mod_stmt);
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
+									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -5944,6 +5958,12 @@ exec_move_row(PLpgSQL_execstate *estate,
 		int			t_natts;
 		int			fnum;
 		int			anum;
+		int			strict_multiassignment_level = 0;
+
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
 
 		if (HeapTupleIsValid(tup))
 			t_natts = HeapTupleHeaderGetNatts(tup->t_data);
@@ -5974,6 +5994,7 @@ exec_move_row(PLpgSQL_execstate *estate,
 					value = SPI_getbinval(tup, tupdesc, anum + 1, &isnull);
 				else
 				{
+					/* there are no data */
 					value = (Datum) 0;
 					isnull = true;
 				}
@@ -5987,12 +6008,37 @@ exec_move_row(PLpgSQL_execstate *estate,
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level >= WARNING)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("Number of evaluated fields does not match expected."),
+								 errhint("strict_multi_assignement check of extra_%s is active.",
+									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When stric_multiassignment extra check is active, then ensure so there
+		 * are not more unassigned columns.
+		 */
+		if (strict_multiassignment_level >= WARNING && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of evaluated fields does not match expected."),
+						 errhint("strict_multi_assignement check of extra_%s is active.",
+							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 4c2ba2f734..c6064299ab 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index c571afa34b..e0ee6172db 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1019,7 +1019,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index 4783807ae0..5946903974 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3089,6 +3089,99 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 768270d467..0e255b88f1 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2605,6 +2605,92 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index c1e3c6a19d..1657ec3fb5 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -4987,7 +4987,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -4999,26 +4999,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>all</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes only one:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as SELECT INTO.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use NULL for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a WARNING or
+        ERROR whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an INTO statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5034,8 +5070,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4ff87e0879..6a1c30e769 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3809,6 +3809,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3847,9 +3853,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -3858,7 +3865,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level >= WARNING)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -3972,19 +3979,26 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level >= WARNING))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				errlevel = stmt->strict || stmt->mod_stmt ? ERROR : too_many_rows_level;
+				use_errhint = !(stmt->strict || stmt->mod_stmt);
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
+									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6602,6 +6616,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6680,10 +6707,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* there are no data */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level >= WARNING)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("Number of evaluated fields does not match expected."),
+									 errhint("strict_multi_assignement check of extra_%s is active.",
+										  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6697,6 +6733,24 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When stric_multiassignment extra check is active, then ensure so there
+			 * are not more unassigned source value.
+			 */
+			if (strict_multiassignment_level >= WARNING && anum < td_natts)
+			{
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;			/* skip dropped column in tuple */
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("Number of evaluated fields does not match expected."),
+							 errhint("strict_multi_assignement check of extra_%s is active.",
+								  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6757,12 +6811,38 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				/* When source value is missing */
+				if (strict_multiassignment_level >= WARNING)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("Number of evaluated fields does not match expected."),
+								 errhint("strict_multi_assignement check of extra_%s is active.",
+									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When stric_multiassignment extra check is active, then ensure so there
+		 * are not more unassigned source value.
+		 */
+		if (strict_multiassignment_level >= WARNING && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of evaluated fields does not match expected."),
+						 errhint("strict_multi_assignement check of extra_%s is active.",
+							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index f38ef04077..08eb530d09 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index 26a7344e9a..c9ad099ab1 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1111,7 +1111,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index 722715049c..254580fc41 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3113,6 +3113,101 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index f405d157bb..ec958cf3b4 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 1657ec3..ebdd0be 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -5027,12 +5027,12 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
       <listitem>
        <para>
         Some <application>PL/PgSQL</application> commands allow assigning values
-        to more than one variable at a time, such as SELECT INTO.  Typically,
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
         the number of target variables and the number of source variables should
-        match, though <application>PL/PgSQL</application> will use NULL for
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
         missing values and extra variables are ignored.  Enabling this check
-        will cause <application>PL/PgSQL</application> to throw a WARNING or
-        ERROR whenever the number of target variables and the number of source
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
         variables are different.
        </para>
       </listitem>
@@ -5044,7 +5044,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
        <para>
         Enabling this check will cause <application>PL/PgSQL</application> to
         check if a given query returns more than one row when an
-        <literal>INTO</literal> clause is used.  As an INTO statement will only
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
         ever use one row, having a query return multiple rows is generally
         either inefficient and/or nondeterministic and therefore is likely an
         error.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 44e8edb..0d9815b 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3867,7 +3867,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt || too_many_rows_level >= WARNING)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -3981,7 +3981,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level >= WARNING))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
 				int			errlevel;
@@ -3997,7 +3997,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
-						 errmsg("query returned more than one row"),
+						 errmsg("SELECT INTO query returned more than one row"),
 						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
 						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
 									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
@@ -6709,17 +6709,17 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
-					/* there are no data */
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
 
 					/* When source value is missing */
-					if (strict_multiassignment_level >= WARNING)
+					if (strict_multiassignment_level)
 							ereport(strict_multiassignment_level,
 									(errcode(ERRCODE_DATATYPE_MISMATCH),
-									 errmsg("Number of evaluated fields does not match expected."),
+									 errmsg("Number of source and target fields in assignment does not match."),
 									 errhint("strict_multi_assignement check of extra_%s is active.",
 										  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 				}
@@ -6736,19 +6736,20 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 
 			/*
-			 * When stric_multiassignment extra check is active, then ensure so there
-			 * are not more unassigned source value.
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
 			 */
-			if (strict_multiassignment_level >= WARNING && anum < td_natts)
+			if (strict_multiassignment_level && anum < td_natts)
 			{
+				/* skip dropped columns in the source descriptor */
 				while (anum < td_natts &&
 					   TupleDescAttr(tupdesc, anum)->attisdropped)
-					anum++;			/* skip dropped column in tuple */
+					anum++;
 
 				if (anum < td_natts)
 					ereport(strict_multiassignment_level,
 							(errcode(ERRCODE_DATATYPE_MISMATCH),
-							 errmsg("Number of evaluated fields does not match expected."),
+							 errmsg("Number of source and target fields in assignment does not match."),
 							 errhint("strict_multi_assignement check of extra_%s is active.",
 								  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
@@ -6809,16 +6810,16 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
 
-				/* When source value is missing */
-				if (strict_multiassignment_level >= WARNING)
+				if (strict_multiassignment_level)
 						ereport(strict_multiassignment_level,
 								(errcode(ERRCODE_DATATYPE_MISMATCH),
-								 errmsg("Number of evaluated fields does not match expected."),
+								 errmsg("Number of source and target fields in assignment does not match."),
 								 errhint("strict_multi_assignement check of extra_%s is active.",
 									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
@@ -6828,10 +6829,10 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 		}
 
 		/*
-		 * When stric_multiassignment extra check is active, then ensure so there
-		 * are not more unassigned source value.
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
 		 */
-		if (strict_multiassignment_level >= WARNING && anum < td_natts)
+		if (strict_multiassignment_level && anum < td_natts)
 		{
 			while (anum < td_natts &&
 				   TupleDescAttr(tupdesc, anum)->attisdropped)
@@ -6840,7 +6841,7 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			if (anum < td_natts)
 				ereport(strict_multiassignment_level,
 						(errcode(ERRCODE_DATATYPE_MISMATCH),
-						 errmsg("Number of evaluated fields does not match expected."),
+						 errmsg("Number of source and target fields in assignment does not match."),
 						 errhint("strict_multi_assignement check of extra_%s is active.",
 							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 		}

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index c1e3c6a19d..ebdd0be7ef 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -4987,7 +4987,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -4999,26 +4999,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>all</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes only one:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5034,8 +5070,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 489484f184..bd0a16aa9b 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3806,6 +3806,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3844,9 +3850,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -3855,7 +3862,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -3969,19 +3976,26 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				errlevel = stmt->strict || stmt->mod_stmt ? ERROR : too_many_rows_level;
+				use_errhint = !(stmt->strict || stmt->mod_stmt);
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
-						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errmsg("SELECT INTO query returned more than one row"),
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
+									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6599,6 +6613,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6677,10 +6704,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("Number of source and target fields in assignment does not match."),
+									 errhint("strict_multi_assignement check of extra_%s is active.",
+										  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6694,6 +6730,25 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
+			 */
+			if (strict_multiassignment_level && anum < td_natts)
+			{
+				/* skip dropped columns in the source descriptor */
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("Number of source and target fields in assignment does not match."),
+							 errhint("strict_multi_assignement check of extra_%s is active.",
+								  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6750,16 +6805,42 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("Number of source and target fields in assignment does not match."),
+								 errhint("strict_multi_assignement check of extra_%s is active.",
+									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
+		 */
+		if (strict_multiassignment_level && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of source and target fields in assignment does not match."),
+						 errhint("strict_multi_assignement check of extra_%s is active.",
+							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index f38ef04077..08eb530d09 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index dd59036de0..c0df4e3214 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1112,7 +1112,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index 722715049c..e3fead6777 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2777,7 +2777,7 @@ begin
   raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
 end$$ language plpgsql;
 select footest();
-ERROR:  query returned more than one row
+ERROR:  SELECT INTO query returned more than one row
 CONTEXT:  PL/pgSQL function footest() line 5 at SQL statement
 create or replace function footest() returns void as $$
 declare x record;
@@ -2850,7 +2850,7 @@ begin
   raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
 end$$ language plpgsql;
 select footest();
-ERROR:  query returned more than one row
+ERROR:  SELECT INTO query returned more than one row
 CONTEXT:  PL/pgSQL function footest() line 5 at SQL statement
 create or replace function footest() returns void as $$
 declare x record;
@@ -2914,7 +2914,7 @@ begin
   raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
 end$$ language plpgsql;
 select footest();
-ERROR:  query returned more than one row
+ERROR:  SELECT INTO query returned more than one row
 DETAIL:  parameters: p1 = '2', p3 = 'foo'
 CONTEXT:  PL/pgSQL function footest() line 8 at SQL statement
 create or replace function footest() returns void as $$
@@ -2925,7 +2925,7 @@ begin
   raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
 end$$ language plpgsql;
 select footest();
-ERROR:  query returned more than one row
+ERROR:  SELECT INTO query returned more than one row
 CONTEXT:  PL/pgSQL function footest() line 5 at SQL statement
 create or replace function footest() returns void as $$
 declare x record;
@@ -2972,7 +2972,7 @@ begin
   raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
 end$$ language plpgsql;
 select footest();
-ERROR:  query returned more than one row
+ERROR:  SELECT INTO query returned more than one row
 CONTEXT:  PL/pgSQL function footest() line 10 at SQL statement
 reset plpgsql.print_strict_params;
 create or replace function footest() returns void as $$
@@ -2988,7 +2988,7 @@ begin
   raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
 end$$ language plpgsql;
 select footest();
-ERROR:  query returned more than one row
+ERROR:  SELECT INTO query returned more than one row
 DETAIL:  parameters: p1 = '2', p3 = 'foo'
 CONTEXT:  PL/pgSQL function footest() line 10 at SQL statement
 -- test warnings and errors
@@ -3113,6 +3113,101 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  SELECT INTO query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  SELECT INTO query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index f405d157bb..ec958cf3b4 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 6c25116538..c95f168250 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -5003,7 +5003,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -5015,26 +5015,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>all</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes only one:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5050,8 +5086,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of evaluated fields does not match expected.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 68da7cf669..d390e4b840 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3929,6 +3929,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3967,9 +3973,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -3978,7 +3985,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -4092,19 +4099,28 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
+				bool		force_error;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				force_error = stmt->strict || stmt->mod_stmt;
+				errlevel = force_error ? ERROR : too_many_rows_level;
+				use_errhint = !force_error;
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
+									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6722,6 +6738,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6800,10 +6829,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("Number of source and target fields in assignment does not match."),
+									 errhint("strict_multi_assignement check of extra_%s is active.",
+										  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6817,6 +6855,25 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
+			 */
+			if (strict_multiassignment_level && anum < td_natts)
+			{
+				/* skip dropped columns in the source descriptor */
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("Number of source and target fields in assignment does not match."),
+							 errhint("strict_multi_assignement check of extra_%s is active.",
+								  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6873,16 +6930,42 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("Number of source and target fields in assignment does not match."),
+								 errhint("strict_multi_assignement check of extra_%s is active.",
+									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
+		 */
+		if (strict_multiassignment_level && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of source and target fields in assignment does not match."),
+						 errhint("strict_multi_assignement check of extra_%s is active.",
+							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index f38ef04077..08eb530d09 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index f7619a63f9..3d015cd571 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1124,7 +1124,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index b687fbfddc..246a586b82 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3113,6 +3113,101 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index e71d072aa9..01239e26be 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 6c25116538..2027e35063 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -5003,7 +5003,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -5015,26 +5015,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>all</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes only one:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5050,8 +5086,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 38ea7a091f..2d3dc66726 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3929,6 +3929,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3967,9 +3973,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -3978,7 +3985,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -4092,19 +4099,28 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
+				bool		force_error;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				force_error = stmt->strict || stmt->mod_stmt;
+				errlevel = force_error ? ERROR : too_many_rows_level;
+				use_errhint = !force_error;
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
+									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6722,6 +6738,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6800,10 +6829,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("Number of source and target fields in assignment does not match."),
+									 errhint("strict_multi_assignement check of extra_%s is active.",
+										  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6817,6 +6855,25 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
+			 */
+			if (strict_multiassignment_level && anum < td_natts)
+			{
+				/* skip dropped columns in the source descriptor */
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("Number of source and target fields in assignment does not match."),
+							 errhint("strict_multi_assignement check of extra_%s is active.",
+								  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6873,16 +6930,42 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("Number of source and target fields in assignment does not match."),
+								 errhint("strict_multi_assignement check of extra_%s is active.",
+									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
+		 */
+		if (strict_multiassignment_level && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of source and target fields in assignment does not match."),
+						 errhint("strict_multi_assignement check of extra_%s is active.",
+							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index f38ef04077..08eb530d09 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index f7619a63f9..3d015cd571 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1124,7 +1124,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index b687fbfddc..246a586b82 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3113,6 +3113,101 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  Number of source and target fields in assignment does not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index e71d072aa9..01239e26be 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 7ed926fd51..807e4a66a1 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -5003,7 +5003,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -5015,26 +5015,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>"all"</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5050,8 +5086,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 38ea7a091f..ad22680086 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3929,6 +3929,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -3967,9 +3973,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -3978,7 +3985,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -4092,19 +4099,28 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
+				bool		force_error;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				force_error = stmt->strict || stmt->mod_stmt;
+				errlevel = force_error ? ERROR : too_many_rows_level;
+				use_errhint = !force_error;
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint("too_many_rows check of extra_%s is active.",
+									  too_many_rows_level == ERROR ? "errors" : "warnings") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6722,6 +6738,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6800,10 +6829,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("Number of source and target fields in assignment do not match."),
+									 errhint("strict_multi_assignement check of extra_%s is active.",
+										  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6817,6 +6855,25 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
+			 */
+			if (strict_multiassignment_level && anum < td_natts)
+			{
+				/* skip dropped columns in the source descriptor */
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("Number of source and target fields in assignment do not match."),
+							 errhint("strict_multi_assignement check of extra_%s is active.",
+								  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6873,16 +6930,42 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("Number of source and target fields in assignment do not match."),
+								 errhint("strict_multi_assignement check of extra_%s is active.",
+									  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
+		 */
+		if (strict_multiassignment_level && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("Number of source and target fields in assignment do not match."),
+						 errhint("strict_multi_assignement check of extra_%s is active.",
+							  strict_multiassignment_level == ERROR ? "errors" : "warnings")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index f38ef04077..08eb530d09 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index f7619a63f9..3d015cd571 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1124,7 +1124,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index b687fbfddc..40d827d20d 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3113,6 +3113,101 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index e71d072aa9..01239e26be 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 5b2aac618e..58cb5d4d8b 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -5050,7 +5050,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -5062,26 +5062,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>"all"</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5097,8 +5133,38 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$
+
+SELECT foo();
+WARNING:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  Number of source and target fields in assignment do not match.
+HINT:  strict_multi_assignement check of extra_warnings is active.
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index e39f7357bd..f9491ad448 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -4020,6 +4020,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -4059,9 +4065,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -4070,7 +4077,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -4187,19 +4194,31 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
+				bool		force_error;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				force_error = stmt->strict || stmt->mod_stmt;
+				errlevel = force_error ? ERROR : too_many_rows_level;
+				use_errhint = !force_error;
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ? errhint(too_many_rows_level == ERROR ?
+				/* translator: %s represent a name of extra check */
+										  gettext_noop("%s check of extra_errors is active.") :
+										  gettext_noop("%s check of extra_warnings is active."),
+										  "too_many_rows") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6835,6 +6854,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6913,10 +6945,22 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("number of source and target fields in assignment do not match"),
+									 errhint(strict_multiassignment_level == ERROR ?
+							/* translator: %s represent a name of extra check */
+										  gettext_noop("%s check of extra_errors is active.") :
+										  gettext_noop("%s check of extra_warnings is active."),
+										  "strict_multi_assignement")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6930,6 +6974,28 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
+			 */
+			if (strict_multiassignment_level && anum < td_natts)
+			{
+				/* skip dropped columns in the source descriptor */
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("number of source and target fields in assignment do not match"),
+							 errhint(strict_multiassignment_level == ERROR ?
+					/* translator: %s represent a name of extra check */
+								  gettext_noop("%s check of extra_errors is active.") :
+								  gettext_noop("%s check of extra_warnings is active."),
+								  "strict_multi_assignement")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6986,16 +7052,48 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("number of source and target fields in assignment do not match"),
+								 errhint(strict_multiassignment_level == ERROR ?
+						/* translator: %s represent a name of extra check */
+									  gettext_noop("%s check of extra_errors is active.") :
+									  gettext_noop("%s check of extra_warnings is active."),
+									  "strict_multi_assignement")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
+		 */
+		if (strict_multiassignment_level && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("number of source and target fields in assignment do not match"),
+						 errhint(strict_multiassignment_level == ERROR ?
+				/* translator: %s represent a name of extra check */
+							  gettext_noop("%s check of extra_errors is active.") :
+							  gettext_noop("%s check of extra_warnings is active."),
+							  "strict_multi_assignement")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 61452d9f7f..7d3647a12d 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index fe617791df..2153ac2f7b 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1137,7 +1137,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index b687fbfddc..6d306cd769 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3113,6 +3113,101 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  too_many_rows check of extra_warnings is active.
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  too_many_rows check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  number of source and target fields in assignment do not match
+HINT:  strict_multi_assignement check of extra_warnings is active.
+WARNING:  number of source and target fields in assignment do not match
+HINT:  strict_multi_assignement check of extra_warnings is active.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  number of source and target fields in assignment do not match
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  number of source and target fields in assignment do not match
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  number of source and target fields in assignment do not match
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  number of source and target fields in assignment do not match
+HINT:  strict_multi_assignement check of extra_errors is active.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index e71d072aa9..01239e26be 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$

diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index d6688e13f4..0bf76beb55 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -5034,7 +5034,7 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
 
   </sect2>
   <sect2 id="plpgsql-extra-checks">
-   <title>Additional Compile-time Checks</title>
+   <title>Additional Compile-time and Run-time Checks</title>
 
    <para>
     To aid the user in finding instances of simple but common problems before
@@ -5046,26 +5046,62 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
     so you are advised to test in a separate development environment.
    </para>
 
- <para>
-  These additional checks are enabled through the configuration variables
-  <varname>plpgsql.extra_warnings</varname> for warnings and
-  <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
-  a comma-separated list of checks, <literal>"none"</literal> or <literal>"all"</literal>.
-  The default is <literal>"none"</literal>. Currently the list of available checks
-  includes only one:
-  <variablelist>
-   <varlistentry>
-    <term><varname>shadowed_variables</varname></term>
-    <listitem>
-     <para>
-      Checks if a declaration shadows a previously defined variable.
-     </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
+   <para>
+    Setting <varname>plpgsql.extra_warnings</varname>, or
+    <varname>plpgsql.extra_errors</varname>, as appropriate, to <literal>"all"</literal>
+    is encouraged in development and/or testing environments.
+   </para>
+
+   <para>
+    These additional checks are enabled through the configuration variables
+    <varname>plpgsql.extra_warnings</varname> for warnings and
+    <varname>plpgsql.extra_errors</varname> for errors. Both can be set either to
+    a comma-separated list of checks, <literal>"none"</literal> or
+    <literal>"all"</literal>. The default is <literal>"none"</literal>. Currently
+    the list of available checks includes:
+    <variablelist>
+     <varlistentry>
+      <term><varname>shadowed_variables</varname></term>
+      <listitem>
+       <para>
+        Checks if a declaration shadows a previously defined variable.
+       </para>
+      </listitem>
+     </varlistentry>
 
-  The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
-  set to <varname>shadowed_variables</varname>:
+     <varlistentry>
+      <term><varname>strict_multi_assignment</varname></term>
+      <listitem>
+       <para>
+        Some <application>PL/PgSQL</application> commands allow assigning values
+        to more than one variable at a time, such as <command>SELECT INTO</command>.  Typically,
+        the number of target variables and the number of source variables should
+        match, though <application>PL/PgSQL</application> will use <literal>NULL</literal> for
+        missing values and extra variables are ignored.  Enabling this check
+        will cause <application>PL/PgSQL</application> to throw a <literal>WARNING</literal> or
+        <literal>ERROR</literal> whenever the number of target variables and the number of source
+        variables are different.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><varname>too_many_rows</varname></term>
+      <listitem>
+       <para>
+        Enabling this check will cause <application>PL/PgSQL</application> to
+        check if a given query returns more than one row when an
+        <literal>INTO</literal> clause is used.  As an <literal>INTO</literal> statement will only
+        ever use one row, having a query return multiple rows is generally
+        either inefficient and/or nondeterministic and therefore is likely an
+        error.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+
+    The following example shows the effect of <varname>plpgsql.extra_warnings</varname>
+    set to <varname>shadowed_variables</varname>:
 <programlisting>
 SET plpgsql.extra_warnings TO 'shadowed_variables';
 
@@ -5081,8 +5117,41 @@ LINE 3: f1 int;
         ^
 CREATE FUNCTION
 </programlisting>
- </para>
- </sect2>
+    The below example shows the effects of setting
+    <varname>plpgsql.extra_warnings</varname> to
+    <varname>strict_multi_assignment</varname>:
+<programlisting>
+SET plpgsql.extra_warnings TO 'strict_multi_assignment';
+
+CREATE OR REPLACE FUNCTION public.foo()
+ RETURNS void
+ LANGUAGE plpgsql
+AS $$
+DECLARE
+  x int;
+  y int;
+BEGIN
+  SELECT 1 INTO x, y;
+  SELECT 1, 2 INTO x, y;
+  SELECT 1, 2, 3 INTO x, y;
+END;
+$$;
+
+SELECT foo();
+WARNING:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_warnings is active.
+HINT:  Make sure the query returns the exact list of columns.
+WARNING:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_warnings is active.
+HINT:  Make sure the query returns the exact list of columns.
+
+ foo 
+-----
+ 
+(1 row)
+</programlisting>
+   </para>
+  </sect2>
  </sect1>
 
   <!-- **** Porting from Oracle PL/SQL **** -->
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index e39f7357bd..8c1a135187 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -4020,6 +4020,12 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	long		tcount;
 	int			rc;
 	PLpgSQL_expr *expr = stmt->sqlstmt;
+	int			too_many_rows_level = 0;
+
+	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = ERROR;
+	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
+		too_many_rows_level = WARNING;
 
 	/*
 	 * On the first call for this statement generate the plan, and detect
@@ -4059,9 +4065,10 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 
 	/*
 	 * If we have INTO, then we only need one row back ... but if we have INTO
-	 * STRICT, ask for two rows, so that we can verify the statement returns
-	 * only one.  INSERT/UPDATE/DELETE are always treated strictly. Without
-	 * INTO, just run the statement to completion (tcount = 0).
+	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
+	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
+	 * treated strictly. Without INTO, just run the statement to completion
+	 * (tcount = 0).
 	 *
 	 * We could just ask for two rows always when using INTO, but there are
 	 * some cases where demanding the extra row costs significant time, eg by
@@ -4070,7 +4077,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 	 */
 	if (stmt->into)
 	{
-		if (stmt->strict || stmt->mod_stmt)
+		if (stmt->strict || stmt->mod_stmt || too_many_rows_level)
 			tcount = 2;
 		else
 			tcount = 1;
@@ -4187,19 +4194,28 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
 		}
 		else
 		{
-			if (n > 1 && (stmt->strict || stmt->mod_stmt))
+			if (n > 1 && (stmt->strict || stmt->mod_stmt || too_many_rows_level))
 			{
 				char	   *errdetail;
+				int			errlevel;
+				bool		use_errhint;
+				bool		force_error;
 
 				if (estate->func->print_strict_params)
 					errdetail = format_expr_params(estate, expr);
 				else
 					errdetail = NULL;
 
-				ereport(ERROR,
+				force_error = stmt->strict || stmt->mod_stmt;
+				errlevel = force_error ? ERROR : too_many_rows_level;
+				use_errhint = !force_error;
+
+				ereport(errlevel,
 						(errcode(ERRCODE_TOO_MANY_ROWS),
 						 errmsg("query returned more than one row"),
-						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0));
+						 errdetail ? errdetail_internal("parameters: %s", errdetail) : 0,
+						 use_errhint ?
+					  errhint("Make sure the query returns a single row, or use LIMIT 1") : 0));
 			}
 			/* Put the first result row into the target */
 			exec_move_row(estate, target, tuptab->vals[0], tuptab->tupdesc);
@@ -6835,6 +6851,19 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 	int			td_natts = tupdesc ? tupdesc->natts : 0;
 	int			fnum;
 	int			anum;
+	int			strict_multiassignment_level = 0;
+
+	/*
+	 * The extra check strict strict_multi_assignment can be active,
+	 * only when input tupdesc is specified.
+	 */
+	if (tupdesc != NULL)
+	{
+		if (plpgsql_extra_errors & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = ERROR;
+		else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT)
+			strict_multiassignment_level = WARNING;
+	}
 
 	/* Handle RECORD-target case */
 	if (target->dtype == PLPGSQL_DTYPE_REC)
@@ -6913,10 +6942,23 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				}
 				else
 				{
+					/* no source for destination column */
 					value = (Datum) 0;
 					isnull = true;
 					valtype = UNKNOWNOID;
 					valtypmod = -1;
+
+					/* When source value is missing */
+					if (strict_multiassignment_level)
+							ereport(strict_multiassignment_level,
+									(errcode(ERRCODE_DATATYPE_MISMATCH),
+									 errmsg("number of source and target fields in assignment do not match"),
+							/* translator: %s represents a name of an extra check */
+									 errdetail("%s check of %s is active.",
+											   "strict_multi_assignment",
+													  strict_multiassignment_level == ERROR ? "extra_errors" :
+																	  "extra_warnings"),
+									 errhint("Make sure the query returns the exact list of columns.")));
 				}
 
 				/* Cast the new value to the right type, if needed. */
@@ -6930,6 +6972,29 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 				newnulls[fnum] = isnull;
 			}
 
+			/*
+			 * When strict_multiassignment extra check is active, then ensure
+			 * there are no unassigned source attributes.
+			 */
+			if (strict_multiassignment_level && anum < td_natts)
+			{
+				/* skip dropped columns in the source descriptor */
+				while (anum < td_natts &&
+					   TupleDescAttr(tupdesc, anum)->attisdropped)
+					anum++;
+
+				if (anum < td_natts)
+					ereport(strict_multiassignment_level,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("number of source and target fields in assignment do not match"),
+					/* translator: %s represents a name of an extra check */
+							 errdetail("%s check of %s is active.",
+									   "strict_multi_assignment",
+										  strict_multiassignment_level == ERROR ? "extra_errors" :
+																	  "extra_warnings"),
+							 errhint("Make sure the query returns the exact list of columns.")));
+			}
+
 			values = newvalues;
 			nulls = newnulls;
 		}
@@ -6986,16 +7051,50 @@ exec_move_row_from_fields(PLpgSQL_execstate *estate,
 			}
 			else
 			{
+				/* no source for destination column */
 				value = (Datum) 0;
 				isnull = true;
 				valtype = UNKNOWNOID;
 				valtypmod = -1;
+
+				if (strict_multiassignment_level)
+						ereport(strict_multiassignment_level,
+								(errcode(ERRCODE_DATATYPE_MISMATCH),
+								 errmsg("number of source and target fields in assignment do not match"),
+				/* translator: %s represents a name of an extra check */
+						 errdetail("%s check of %s is active.",
+								  "strict_multi_assignment",
+								  strict_multiassignment_level == ERROR ? "extra_errors" :
+																	  "extra_warnings"),
+								 errhint("Make sure the query returns the exact list of columns.")));
 			}
 
 			exec_assign_value(estate, (PLpgSQL_datum *) var,
 							  value, isnull, valtype, valtypmod);
 		}
 
+		/*
+		 * When strict_multiassignment extra check is active, ensure there
+		 * are no unassigned source attributes.
+		 */
+		if (strict_multiassignment_level && anum < td_natts)
+		{
+			while (anum < td_natts &&
+				   TupleDescAttr(tupdesc, anum)->attisdropped)
+				anum++;			/* skip dropped column in tuple */
+
+			if (anum < td_natts)
+				ereport(strict_multiassignment_level,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("number of source and target fields in assignment do not match"),
+				/* translator: %s represents a name of an extra check */
+						 errdetail("%s check of %s is active.",
+								  "strict_multi_assignment",
+								  strict_multiassignment_level == ERROR ? "extra_errors" :
+																	  "extra_warnings"),
+						 errhint("Make sure the query returns the exact list of columns.")));
+		}
+
 		return;
 	}
 
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 61452d9f7f..7d3647a12d 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -92,6 +92,10 @@ plpgsql_extra_checks_check_hook(char **newvalue, void **extra, GucSource source)
 
 			if (pg_strcasecmp(tok, "shadowed_variables") == 0)
 				extrachecks |= PLPGSQL_XCHECK_SHADOWVAR;
+			else if (pg_strcasecmp(tok, "too_many_rows") == 0)
+				extrachecks |= PLPGSQL_XCHECK_TOOMANYROWS;
+			else if (pg_strcasecmp(tok, "strict_multi_assignment") == 0)
+				extrachecks |= PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT;
 			else if (pg_strcasecmp(tok, "all") == 0 || pg_strcasecmp(tok, "none") == 0)
 			{
 				GUC_check_errdetail("Key word \"%s\" cannot be combined with other key words.", tok);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index fe617791df..2153ac2f7b 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1137,7 +1137,9 @@ extern bool plpgsql_check_asserts;
 
 /* extra compile-time checks */
 #define PLPGSQL_XCHECK_NONE			0
-#define PLPGSQL_XCHECK_SHADOWVAR	1
+#define PLPGSQL_XCHECK_SHADOWVAR	(1 << 1)
+#define PLPGSQL_XCHECK_TOOMANYROWS	(1 << 2)
+#define PLPGSQL_XCHECK_STRICTMULTIASSIGNMENT	(1 << 3)
 #define PLPGSQL_XCHECK_ALL			((int) ~0)
 
 extern int	plpgsql_extra_warnings;
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index b687fbfddc..2b86c8f7ac 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -3113,6 +3113,107 @@ select shadowtest(1);
  t
 (1 row)
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+WARNING:  query returned more than one row
+HINT:  Make sure the query returns a single row, or use LIMIT 1
+set plpgsql.extra_errors to 'too_many_rows';
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+ERROR:  query returned more than one row
+HINT:  Make sure the query returns a single row, or use LIMIT 1
+CONTEXT:  PL/pgSQL function inline_code_block line 4 at SQL statement
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+WARNING:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_warnings is active.
+HINT:  Make sure the query returns the exact list of columns.
+WARNING:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_warnings is active.
+HINT:  Make sure the query returns the exact list of columns.
+set plpgsql.extra_errors to 'strict_multi_assignment';
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+ERROR:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_errors is active.
+HINT:  Make sure the query returns the exact list of columns.
+CONTEXT:  PL/pgSQL function inline_code_block line 6 at SQL statement
+create table test_01(a int, b int, c int);
+alter table test_01 drop column a;
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+NOTICE:  ok
+ERROR:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_errors is active.
+HINT:  Make sure the query returns the exact list of columns.
+CONTEXT:  PL/pgSQL function inline_code_block line 8 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+NOTICE:  ok
+ERROR:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_errors is active.
+HINT:  Make sure the query returns the exact list of columns.
+CONTEXT:  PL/pgSQL function inline_code_block line 7 at SQL statement
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+ERROR:  number of source and target fields in assignment do not match
+DETAIL:  strict_multi_assignment check of extra_errors is active.
+HINT:  Make sure the query returns the exact list of columns.
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at SQL statement
+drop table test_01;
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
 -- test scrollable cursor support
 create function sc_test() returns setof integer as $$
 declare
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index e71d072aa9..01239e26be 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2627,6 +2627,95 @@ declare f1 int; begin return 1; end $$ language plpgsql;
 
 select shadowtest(1);
 
+-- runtime extra checks
+set plpgsql.extra_warnings to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+set plpgsql.extra_errors to 'too_many_rows';
+
+do $$
+declare x int;
+begin
+  select v from generate_series(1,2) g(v) into x;
+end;
+$$;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
+set plpgsql.extra_warnings to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+set plpgsql.extra_errors to 'strict_multi_assignment';
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select 1 into x, y;
+  select 1,2 into x, y;
+  select 1,2,3 into x, y;
+end
+$$;
+
+create table test_01(a int, b int, c int);
+
+alter table test_01 drop column a;
+
+-- the check is active only when source table is not empty
+insert into test_01 values(10,20);
+
+do $$
+declare
+  x int;
+  y int;
+begin
+  select * from test_01 into x, y; -- should be ok
+  raise notice 'ok';
+  select * from test_01 into x;    -- should to fail
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1, 2 into t;  -- should be ok
+  raise notice 'ok';
+  select 1, 2, 3 into t; -- should fail;
+end;
+$$;
+
+do $$
+declare
+  t test_01;
+begin
+  select 1 into t; -- should fail;
+end;
+$$;
+
+drop table test_01;
+
+reset plpgsql.extra_errors;
+reset plpgsql.extra_warnings;
+
 -- test scrollable cursor support
 
 create function sc_test() returns setof integer as $$