From 616f674c81ae5aa07fad40f976050e56ffd1c339 Mon Sep 17 00:00:00 2001
From: Yugo Nagata <nagata@sraoss.co.jp>
Date: Wed, 31 Jul 2024 17:34:15 +0900
Subject: [PATCH v2 1/3] Small refactoring around ExecCreateTableAs

Since commit b4da732f, the refresh logic is used to populate
materialized views, so we can simplify the error message
in ExecCreateTableAs.

In addition, we can remove matview-related codes from
intorel_startup because materialized views are no longer handled
in this function.

Also, RefreshMatViewByOid is moved to just after create_ctas_nodata
call to improve code readability.
---
 src/backend/commands/createas.c | 47 +++++++++++----------------------
 1 file changed, 16 insertions(+), 31 deletions(-)

diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c
index 2c8a93b6e5..68d5047924 100644
--- a/src/backend/commands/createas.c
+++ b/src/backend/commands/createas.c
@@ -228,9 +228,6 @@ ExecCreateTableAs(ParseState *pstate, CreateTableAsStmt *stmt,
 	bool		do_refresh = false;
 	DestReceiver *dest;
 	ObjectAddress address;
-	List	   *rewritten;
-	PlannedStmt *plan;
-	QueryDesc  *queryDesc;
 
 	/* Check if the relation exists or not */
 	if (CreateTableAsRelExists(stmt))
@@ -279,9 +276,24 @@ ExecCreateTableAs(ParseState *pstate, CreateTableAsStmt *stmt,
 		 * from running the planner before all dependencies are set up.
 		 */
 		address = create_ctas_nodata(query->targetList, into);
+
+		/*
+		 * For materialized views, reuse the REFRESH logic, which locks down
+		 * security-restricted operations and restricts the search_path.  This
+		 * reduces the chance that a subsequent refresh will fail.
+		 */
+		if (do_refresh)
+			RefreshMatViewByOid(address.objectId, false, false,
+								pstate->p_sourcetext, NULL qc);
 	}
 	else
 	{
+		List	   *rewritten;
+		PlannedStmt *plan;
+		QueryDesc  *queryDesc;
+
+		Assert(!is_matview);
+
 		/*
 		 * Parse analysis was done already, but we still have to run the rule
 		 * rewriter.  We do not do AcquireRewriteLocks: we assume the query
@@ -292,9 +304,7 @@ ExecCreateTableAs(ParseState *pstate, CreateTableAsStmt *stmt,
 
 		/* SELECT should never rewrite to more or less than one SELECT query */
 		if (list_length(rewritten) != 1)
-			elog(ERROR, "unexpected rewrite result for %s",
-				 is_matview ? "CREATE MATERIALIZED VIEW" :
-				 "CREATE TABLE AS SELECT");
+			elog(ERROR, "unexpected rewrite result for CREATE TABLE AS SELECT");
 		query = linitial_node(Query, rewritten);
 		Assert(query->commandType == CMD_SELECT);
 
@@ -339,20 +349,6 @@ ExecCreateTableAs(ParseState *pstate, CreateTableAsStmt *stmt,
 		PopActiveSnapshot();
 	}
 
-	/*
-	 * For materialized views, reuse the REFRESH logic, which locks down
-	 * security-restricted operations and restricts the search_path.  This
-	 * reduces the chance that a subsequent refresh will fail.
-	 */
-	if (do_refresh)
-	{
-		RefreshMatViewByOid(address.objectId, false, false,
-							pstate->p_sourcetext, NULL, qc);
-
-		if (qc)
-			qc->commandTag = CMDTAG_SELECT;
-	}
-
 	return address;
 }
 
@@ -453,7 +449,6 @@ intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
 {
 	DR_intorel *myState = (DR_intorel *) self;
 	IntoClause *into = myState->into;
-	bool		is_matview;
 	List	   *attrList;
 	ObjectAddress intoRelationAddr;
 	Relation	intoRelationDesc;
@@ -462,9 +457,6 @@ intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
 
 	Assert(into != NULL);		/* else somebody forgot to set it */
 
-	/* This code supports both CREATE TABLE AS and CREATE MATERIALIZED VIEW */
-	is_matview = (into->viewQuery != NULL);
-
 	/*
 	 * Build column definitions using "pre-cooked" type and collation info. If
 	 * a column name list was specified in CREATE TABLE AS, override the
@@ -538,13 +530,6 @@ intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("policies not yet implemented for this command")));
 
-	/*
-	 * Tentatively mark the target as populated, if it's a matview and we're
-	 * going to fill it; otherwise, no change needed.
-	 */
-	if (is_matview && !into->skipData)
-		SetMatViewPopulatedState(intoRelationDesc, true);
-
 	/*
 	 * Fill private fields of myState for use by later routines
 	 */
-- 
2.34.1