From ce6d3bbdac073b4750745120f9a754c30bd57b66 Mon Sep 17 00:00:00 2001
From: Erik Wienhold <ewie@ewie.name>
Date: Tue, 28 May 2024 02:19:53 +0200
Subject: [PATCH v4 2/3] Deprecate CREATE MATERIALIZED VIEW IF NOT EXISTS

---
 src/backend/parser/gram.y                     | 14 ++++++
 .../expected/test_extensions.out              | 45 +++++++++++++++++++
 src/test/regress/expected/matview.out         | 20 +++++++++
 3 files changed, 79 insertions(+)

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 6b32233127..dadc6b630a 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -4808,6 +4808,20 @@ CreateMatViewStmt:
 					$8->rel->relpersistence = $2;
 					$8->skipData = !($11);
 					$$ = (Node *) ctas;
+
+					if (ctas->into->rel->schemaname)
+							ereport(WARNING,
+									errmsg("IF NOT EXISTS is deprecated in materialized view creation"),
+									errhint("Use CREATE OR REPLACE MATERIALIZED VIEW %s.%s.",
+											ctas->into->rel->schemaname,
+											ctas->into->rel->relname),
+									parser_errposition(@1));
+					else
+							ereport(WARNING,
+									errmsg("IF NOT EXISTS is deprecated in materialized view creation"),
+									errhint("Use CREATE OR REPLACE MATERIALIZED VIEW %s.",
+											ctas->into->rel->relname),
+									parser_errposition(@1));
 				}
 		| CREATE OR REPLACE OptNoLog MATERIALIZED VIEW create_mv_target AS SelectStmt opt_with_data
 				{
diff --git a/src/test/modules/test_extensions/expected/test_extensions.out b/src/test/modules/test_extensions/expected/test_extensions.out
index d5388a1fec..9a1e0f7658 100644
--- a/src/test/modules/test_extensions/expected/test_extensions.out
+++ b/src/test/modules/test_extensions/expected/test_extensions.out
@@ -404,6 +404,11 @@ Objects in extension "test_ext_cor"
 CREATE COLLATION ext_cine_coll
   ( LC_COLLATE = "C", LC_CTYPE = "C" );
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  collation ext_cine_coll is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE COLLATION IF NOT EXISTS ext_cine_coll
@@ -412,6 +417,11 @@ extension script file "test_ext_cine--1.0.sql", near line 10
 DROP COLLATION ext_cine_coll;
 CREATE MATERIALIZED VIEW ext_cine_mv AS SELECT 11 AS f1;
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  materialized view ext_cine_mv is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1"
@@ -420,6 +430,11 @@ DROP MATERIALIZED VIEW ext_cine_mv;
 CREATE FOREIGN DATA WRAPPER dummy;
 CREATE SERVER ext_cine_srv FOREIGN DATA WRAPPER dummy;
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  server ext_cine_srv is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE SERVER IF NOT EXISTS ext_cine_srv FOREIGN DATA WRAPPER ext_cine_fdw"
@@ -427,6 +442,11 @@ extension script file "test_ext_cine--1.0.sql", near line 17
 DROP SERVER ext_cine_srv;
 CREATE SCHEMA ext_cine_schema;
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  schema ext_cine_schema is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE SCHEMA IF NOT EXISTS ext_cine_schema"
@@ -434,6 +454,11 @@ extension script file "test_ext_cine--1.0.sql", near line 19
 DROP SCHEMA ext_cine_schema;
 CREATE SEQUENCE ext_cine_seq;
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  sequence ext_cine_seq is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE SEQUENCE IF NOT EXISTS ext_cine_seq"
@@ -441,6 +466,11 @@ extension script file "test_ext_cine--1.0.sql", near line 21
 DROP SEQUENCE ext_cine_seq;
 CREATE TABLE ext_cine_tab1 (x int);
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  table ext_cine_tab1 is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE TABLE IF NOT EXISTS ext_cine_tab1 (x int)"
@@ -448,12 +478,22 @@ extension script file "test_ext_cine--1.0.sql", near line 23
 DROP TABLE ext_cine_tab1;
 CREATE TABLE ext_cine_tab2 AS SELECT 42 AS y;
 CREATE EXTENSION test_ext_cine;  -- fail
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 ERROR:  table ext_cine_tab2 is not a member of extension "test_ext_cine"
 DETAIL:  An extension may only use CREATE ... IF NOT EXISTS to skip object creation if the conflicting object is one that it already owns.
 CONTEXT:  SQL statement "CREATE TABLE IF NOT EXISTS ext_cine_tab2 AS SELECT 42 AS y"
 extension script file "test_ext_cine--1.0.sql", near line 25
 DROP TABLE ext_cine_tab2;
 CREATE EXTENSION test_ext_cine;
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 \dx+ test_ext_cine
 Objects in extension "test_ext_cine"
         Object description         
@@ -475,6 +515,11 @@ Objects in extension "test_ext_cine"
 (14 rows)
 
 ALTER EXTENSION test_ext_cine UPDATE TO '1.1';
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW ext_cine_mv.
+QUERY:  CREATE MATERIALIZED VIEW IF NOT EXISTS ext_cine_mv AS SELECT 42 AS f1;
 \dx+ test_ext_cine
 Objects in extension "test_ext_cine"
         Object description         
diff --git a/src/test/regress/expected/matview.out b/src/test/regress/expected/matview.out
index e2e2a13396..cefd0d442c 100644
--- a/src/test/regress/expected/matview.out
+++ b/src/test/regress/expected/matview.out
@@ -565,6 +565,10 @@ CREATE MATERIALIZED VIEW mvtest_mv_foo AS SELECT * FROM mvtest_foo_data;
 CREATE MATERIALIZED VIEW mvtest_mv_foo AS SELECT * FROM mvtest_foo_data;
 ERROR:  relation "mvtest_mv_foo" already exists
 CREATE MATERIALIZED VIEW IF NOT EXISTS mvtest_mv_foo AS SELECT * FROM mvtest_foo_data;
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS mvtest_mv_foo AS SELE...
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW mvtest_mv_foo.
 NOTICE:  relation "mvtest_mv_foo" already exists, skipping
 CREATE UNIQUE INDEX ON mvtest_mv_foo (i);
 RESET ROLE;
@@ -662,12 +666,20 @@ CREATE MATERIALIZED VIEW matview_ine_tab AS SELECT 1 / 0; -- error
 ERROR:  relation "matview_ine_tab" already exists
 CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
   SELECT 1 / 0; -- ok
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW matview_ine_tab.
 NOTICE:  relation "matview_ine_tab" already exists, skipping
 CREATE MATERIALIZED VIEW matview_ine_tab AS
   SELECT 1 / 0 WITH NO DATA; -- error
 ERROR:  relation "matview_ine_tab" already exists
 CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
   SELECT 1 / 0 WITH NO DATA; -- ok
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 1: CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
+        ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW matview_ine_tab.
 NOTICE:  relation "matview_ine_tab" already exists, skipping
 EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
   CREATE MATERIALIZED VIEW matview_ine_tab AS
@@ -676,6 +688,10 @@ ERROR:  relation "matview_ine_tab" already exists
 EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
   CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
     SELECT 1 / 0; -- ok
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 2:   CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
+          ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW matview_ine_tab.
 NOTICE:  relation "matview_ine_tab" already exists, skipping
  QUERY PLAN 
 ------------
@@ -688,6 +704,10 @@ ERROR:  relation "matview_ine_tab" already exists
 EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
   CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
     SELECT 1 / 0 WITH NO DATA; -- ok
+WARNING:  IF NOT EXISTS is deprecated in materialized view creation
+LINE 2:   CREATE MATERIALIZED VIEW IF NOT EXISTS matview_ine_tab AS
+          ^
+HINT:  Use CREATE OR REPLACE MATERIALIZED VIEW matview_ine_tab.
 NOTICE:  relation "matview_ine_tab" already exists, skipping
  QUERY PLAN 
 ------------
-- 
2.47.0

