From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Sat, 18 Sep 1999 23:30:05 +0000 (+0000)
Subject: Back-patch fix for NULL condition in CASE.
X-Git-Url: http://waps.l3s.uni-hannover.de/gitweb/?a=commitdiff_plain;h=9a7d8a20b66ef0808ba08f55dd10137cc877dc1a;p=users%2Fbernd%2Fpostgres.git

Back-patch fix for NULL condition in CASE.
---

diff --git a/src/backend/executor/execQual.c b/src/backend/executor/execQual.c
index 5f6787b7cb..2b8b47cc80 100644
--- a/src/backend/executor/execQual.c
+++ b/src/backend/executor/execQual.c
@@ -1128,9 +1128,10 @@ ExecEvalCase(CaseExpr *caseExpr, ExprContext *econtext, bool *isNull)
 
 		/*
 		 * if we have a true test, then we return the result, since the
-		 * case statement is satisfied.
+		 * case statement is satisfied.  A NULL result from the test is
+		 * not considered true.
 		 */
-		if (DatumGetInt32(const_value) != 0)
+		if (DatumGetInt32(const_value) != 0 && ! *isNull)
 		{
 			const_value = ExecEvalExpr((Node *) wclause->result,
 									   econtext,