diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 91fadb0..a3c763a 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -3403,6 +3403,8 @@ RAISE ;
     Inside the format string, <literal>%</literal> is replaced by the
     string representation of the next optional argument's value. Write
     <literal>%%</literal> to emit a literal <literal>%</literal>.
+    The number of optional arguments must match the number of <literal>%</>
+    placeholders in the format string, otherwise a compilation error is reported.
    </para>
 
    <para>
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 69d1965..a3cd6fc 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -2939,6 +2939,10 @@ exec_stmt_raise(PLpgSQL_execstate *estate, PLpgSQL_stmt_raise *stmt)
 					continue;
 				}
 
+				/*
+				 * Too few arguments to "raise":
+				 * This should never happen as a compile-time check is performed.
+				 */
 				if (current_param == NULL)
 					ereport(ERROR,
 							(errcode(ERRCODE_SYNTAX_ERROR),
@@ -2965,7 +2969,8 @@ exec_stmt_raise(PLpgSQL_execstate *estate, PLpgSQL_stmt_raise *stmt)
 
 		/*
 		 * If more parameters were specified than were required to process the
-		 * format string, throw an error
+		 * format string, throw an error.
+		 * This should never happen as a compile-time check is performed.
 		 */
 		if (current_param != NULL)
 			ereport(ERROR,
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
index ba928e3..03976e4 100644
--- a/src/pl/plpgsql/src/pl_gram.y
+++ b/src/pl/plpgsql/src/pl_gram.y
@@ -3785,15 +3785,12 @@ check_raise_parameters(PLpgSQL_stmt_raise *stmt)
 
 	for (cp = stmt->message; *cp; cp++)
 	{
-		if (cp[0] != '%')
-			continue;
-		/* literal %, ignore */
-		if (cp[1] == '%')
-		{
-			cp++;
-			continue;
+		if (cp[0] == '%') {
+			if (cp[1] == '%') /* literal %, ignore */
+				cp++;
+			else
+				expected_nparams++;
 		}
-		expected_nparams++;
 	}
 
 	if (expected_nparams < list_length(stmt->params))