0001-Fix-alias-collision-for-REFRESH-MV-CONCURRENTLY.patch

From 121b06258b80e5097c963335794e9a89f7e6d3ec Mon Sep 17 00:00:00 2001
From: Mathis Rudolf <mathis.rudolf@credativ.de>
Date: Mon, 17 May 2021 14:55:49 +0200
Subject: [PATCH] Fix alias collision for REFRESH MV CONCURRENTLY

This patch adds the prefix _pg_internal_ to aliases like 'mv' and
'newdata' in 'refresh_by_match_merge()', which makes it unliky to cause
any collisions with user created MVs.
---
 src/backend/commands/matview.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c
index 172ec6e982..04602dba80 100644
--- a/src/backend/commands/matview.c
+++ b/src/backend/commands/matview.c
@@ -629,12 +629,12 @@ refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
 	 */
 	resetStringInfo(&querybuf);
 	appendStringInfo(&querybuf,
-					 "SELECT newdata FROM %s newdata "
-					 "WHERE newdata IS NOT NULL AND EXISTS "
-					 "(SELECT 1 FROM %s newdata2 WHERE newdata2 IS NOT NULL "
-					 "AND newdata2 OPERATOR(pg_catalog.*=) newdata "
-					 "AND newdata2.ctid OPERATOR(pg_catalog.<>) "
-					 "newdata.ctid)",
+					 "SELECT pg_internal_newdata FROM %s pg_internal_newdata "
+					 "WHERE pg_internal_newdata IS NOT NULL AND EXISTS "
+					 "(SELECT 1 FROM %s pg_internal_newdata2 WHERE pg_internal_newdata2 IS NOT NULL "
+					 "AND pg_internal_newdata2 OPERATOR(pg_catalog.*=) pg_internal_newdata "
+					 "AND pg_internal_newdata2.ctid OPERATOR(pg_catalog.<>) "
+					 "pg_internal_newdata.ctid)",
 					 tempname, tempname);
 	if (SPI_execute(querybuf.data, false, 1) != SPI_OK_SELECT)
 		elog(ERROR, "SPI_exec failed: %s", querybuf.data);
@@ -662,8 +662,8 @@ refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
 	resetStringInfo(&querybuf);
 	appendStringInfo(&querybuf,
 					 "CREATE TEMP TABLE %s AS "
-					 "SELECT mv.ctid AS tid, newdata "
-					 "FROM %s mv FULL JOIN %s newdata ON (",
+					 "SELECT pg_internal_mv.ctid AS tid, pg_internal_newdata "
+					 "FROM %s pg_internal_mv FULL JOIN %s pg_internal_newdata ON (",
 					 diffname, matviewname, tempname);
 
 	/*
@@ -756,9 +756,9 @@ refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
 				if (foundUniqueIndex)
 					appendStringInfoString(&querybuf, " AND ");
 
-				leftop = quote_qualified_identifier("newdata",
+				leftop = quote_qualified_identifier("pg_internal_newdata",
 													NameStr(attr->attname));
-				rightop = quote_qualified_identifier("mv",
+				rightop = quote_qualified_identifier("pg_internal_mv",
 													 NameStr(attr->attname));
 
 				generate_operator_clause(&querybuf,
@@ -786,8 +786,8 @@ refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
 	Assert(foundUniqueIndex);
 
 	appendStringInfoString(&querybuf,
-						   " AND newdata OPERATOR(pg_catalog.*=) mv) "
-						   "WHERE newdata IS NULL OR mv IS NULL "
+						   " AND pg_internal_newdata OPERATOR(pg_catalog.*=) pg_internal_mv) "
+						   "WHERE pg_internal_newdata IS NULL OR pg_internal_mv IS NULL "
 						   "ORDER BY tid");
 
 	/* Create the temporary "diff" table. */
@@ -813,10 +813,10 @@ refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
 	/* Deletes must come before inserts; do them first. */
 	resetStringInfo(&querybuf);
 	appendStringInfo(&querybuf,
-					 "DELETE FROM %s mv WHERE ctid OPERATOR(pg_catalog.=) ANY "
+					 "DELETE FROM %s pg_internal_mv WHERE ctid OPERATOR(pg_catalog.=) ANY "
 					 "(SELECT diff.tid FROM %s diff "
 					 "WHERE diff.tid IS NOT NULL "
-					 "AND diff.newdata IS NULL)",
+					 "AND diff.pg_internal_newdata IS NULL)",
 					 matviewname, diffname);
 	if (SPI_exec(querybuf.data, 0) != SPI_OK_DELETE)
 		elog(ERROR, "SPI_exec failed: %s", querybuf.data);
@@ -824,7 +824,7 @@ refresh_by_match_merge(Oid matviewOid, Oid tempOid, Oid relowner,
 	/* Inserts go last. */
 	resetStringInfo(&querybuf);
 	appendStringInfo(&querybuf,
-					 "INSERT INTO %s SELECT (diff.newdata).* "
+					 "INSERT INTO %s SELECT (diff.pg_internal_newdata).* "
 					 "FROM %s diff WHERE tid IS NULL",
 					 matviewname, diffname);
 	if (SPI_exec(querybuf.data, 0) != SPI_OK_INSERT)
-- 
2.31.1