Revert "Propagate CTE property flags when copying a CTE list into a rule."

This reverts commit ed290896335414c6c069b9ccae1f3dcdd2fac6ba and
equivalent back-branch commits.  The issue is subtler than I thought,
and it's far from new, so just before a release deadline is no time
to be fooling with it.  We'll consider what to do at a bit more
leisure.

Discussion: https://postgr.es/m/CAJcOf-fAdj=nDKMsRhQzndm-O13NY4dL6xGcEvdX5Xvbbi0V7g@mail.gmail.com

diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c
index 4373b95862f1472a778bc408641be759aacf4e21..d54fdd27fa0518d12701bf78dd2be6d70c639b77 100644 (file)
--- a/src/backend/rewrite/rewriteHandler.c
+++ b/src/backend/rewrite/rewriteHandler.c
@@ -526,9 +526,6 @@ rewriteRuleAction(Query *parsetree,
                 *
                 * This could possibly be fixed by using some sort of internally
                 * generated ID, instead of names, to link CTE RTEs to their CTEs.
-                * However, decompiling the results would be quite confusing; note the
-                * merge of hasRecursive flags below, which could change the apparent
-                * semantics of such redundantly-named CTEs.
                 */
                foreach(lc, parsetree->cteList)
                {
@@ -550,9 +547,6 @@ rewriteRuleAction(Query *parsetree,
                /* OK, it's safe to combine the CTE lists */
                sub_action->cteList = list_concat(sub_action->cteList,
                                                                                  copyObject(parsetree->cteList));
-               /* ... and don't forget about the associated flags */
-               sub_action->hasRecursive |= parsetree->hasRecursive;
-               sub_action->hasModifyingCTE |= parsetree->hasModifyingCTE;
        }
 
        /*

diff --git a/src/test/regress/expected/with.out b/src/test/regress/expected/with.out
index 4f293c4c19419a4b5846e4551c2064f1402a73dd..0646451fb0bc9b54765dad6b38d6522ed857ed5d 100644 (file)
--- a/src/test/regress/expected/with.out
+++ b/src/test/regress/expected/with.out
@@ -1672,33 +1672,6 @@ SELECT * FROM bug6051_2;
  3
 (3 rows)
 
--- silly example to verify that hasModifyingCTE flag is propagated
-CREATE TEMP TABLE bug6051_3 AS
-  select a from generate_series(11,13) as a;
-CREATE RULE bug6051_3_ins AS ON INSERT TO bug6051_3 DO INSTEAD
-  SELECT i FROM bug6051_2;
-BEGIN; SET LOCAL force_parallel_mode = on;
-WITH t1 AS ( DELETE FROM bug6051_3 RETURNING * )
-  INSERT INTO bug6051_3 SELECT * FROM t1;
- i 
----
- 1
- 2
- 3
- 1
- 2
- 3
- 1
- 2
- 3
-(9 rows)
-
-COMMIT;
-SELECT * FROM bug6051_3;
- a 
----
-(0 rows)
-
 -- a truly recursive CTE in the same list
 WITH RECURSIVE t(a) AS (
        SELECT 0

diff --git a/src/test/regress/sql/with.sql b/src/test/regress/sql/with.sql
index 47159e57f70387d886dc53a82ffdd10beea2a65e..512ff1b3ba20c46e456e423203d587254e4ceb1e 100644 (file)
--- a/src/test/regress/sql/with.sql
+++ b/src/test/regress/sql/with.sql
@@ -773,22 +773,6 @@ INSERT INTO bug6051 SELECT * FROM t1;
 SELECT * FROM bug6051;
 SELECT * FROM bug6051_2;
 
--- silly example to verify that hasModifyingCTE flag is propagated
-CREATE TEMP TABLE bug6051_3 AS
-  select a from generate_series(11,13) as a;
-
-CREATE RULE bug6051_3_ins AS ON INSERT TO bug6051_3 DO INSTEAD
-  SELECT i FROM bug6051_2;
-
-BEGIN; SET LOCAL force_parallel_mode = on;
-
-WITH t1 AS ( DELETE FROM bug6051_3 RETURNING * )
-  INSERT INTO bug6051_3 SELECT * FROM t1;
-
-COMMIT;
-
-SELECT * FROM bug6051_3;
-
 -- a truly recursive CTE in the same list
 WITH RECURSIVE t(a) AS (
        SELECT 0