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

tglsfdc · tglsfdc · commit a64aacf152fc · 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
@@ -504,9 +504,6 @@ 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)
 		{
@@ -528,9 +525,6 @@ 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
`@@ -504,9 +504,6 @@ rewriteRuleAction(Query *parsetree,`
`504`	`504`	`*`
`505`	`505`	`* This could possibly be fixed by using some sort of internally`
`506`	`506`	`* generated ID, instead of names, to link CTE RTEs to their CTEs.`
`507`		`- * However, decompiling the results would be quite confusing; note the`
`508`		`- * merge of hasRecursive flags below, which could change the apparent`
`509`		`- * semantics of such redundantly-named CTEs.`
`510`	`507`	`*/`
`511`	`508`	`foreach(lc, parsetree->cteList)`
`512`	`509`	`{`
`@@ -528,9 +525,6 @@ rewriteRuleAction(Query *parsetree,`
`528`	`525`	`/* OK, it's safe to combine the CTE lists */`
`529`	`526`	`sub_action->cteList = list_concat(sub_action->cteList,`
`530`	`527`	`copyObject(parsetree->cteList));`
`531`		`- /* ... and don't forget about the associated flags */`
`532`		`- sub_action->hasRecursive \|= parsetree->hasRecursive;`
`533`		`- sub_action->hasModifyingCTE \|= parsetree->hasModifyingCTE;`
`534`	`528`	`}`
`535`	`529`
`536`	`530`	`/*`