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

tglsfdc · tglsfdc · commit 6f8e393a79e4 · 2021-02-07T12:54:08.000-05:00
This reverts commit ed29089 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
@@ -511,9 +511,6 @@ 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)
 		{
@@ -535,9 +532,6 @@ 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;
 	}
 
 	/*

Original file line number	Diff line number	Diff line change
`@@ -511,9 +511,6 @@ rewriteRuleAction(Query *parsetree,`
`511`	`511`	`*`
`512`	`512`	`* This could possibly be fixed by using some sort of internally`
`513`	`513`	`* generated ID, instead of names, to link CTE RTEs to their CTEs.`
`514`		`- * However, decompiling the results would be quite confusing; note the`
`515`		`- * merge of hasRecursive flags below, which could change the apparent`
`516`		`- * semantics of such redundantly-named CTEs.`
`517`	`514`	`*/`
`518`	`515`	`foreach(lc, parsetree->cteList)`
`519`	`516`	`{`
`@@ -535,9 +532,6 @@ rewriteRuleAction(Query *parsetree,`
`535`	`532`	`/* OK, it's safe to combine the CTE lists */`
`536`	`533`	`sub_action->cteList = list_concat(sub_action->cteList,`
`537`	`534`	`copyObject(parsetree->cteList));`
`538`		`- /* ... and don't forget about the associated flags */`
`539`		`- sub_action->hasRecursive \|= parsetree->hasRecursive;`
`540`		`- sub_action->hasModifyingCTE \|= parsetree->hasModifyingCTE;`
`541`	`535`	`}`
`542`	`536`
`543`	`537`	`/*`