postgres.git / summary / log / commit / refs

commit    b2edbbd02d3070c234225da7b2ec10298652658a
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Mon Dec 31 17:39:15 2018 +0000
First released in: 12.0

    Fix oversight in commit b5415e3c2187ab304390524f5ae66b4bd2c58279.
    
    While rearranging code in tidpath.c, I overlooked the fact that we ought
    to check restriction_is_securely_promotable when trying to use a join
    clause as a TID qual.  Since tideq itself is leakproof, this wouldn't
    really allow any interesting leak AFAICT, but it still seems like we
    had better check it.
    
    For consistency with the corresponding logic in indxpath.c, also
    check rinfo->pseudoconstant.  I'm not sure right now that it's
    possible for that to be set in a join clause, but if it were,
    a match couldn't be made anyway.


 src/backend/optimizer/path/tidpath.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/backend/optimizer/path/tidpath.c b/src/backend/optimizer/path/tidpath.c
index 335de0a4c1d..4d39fa128d7 100644
--- a/src/backend/optimizer/path/tidpath.c
+++ b/src/backend/optimizer/path/tidpath.c
@@ -329,9 +329,14 @@ BuildParameterizedTidPaths(PlannerInfo *root, RelOptInfo *rel, List *clauses)
 		 *
 		 * We currently consider only TidEqual join clauses.  In principle we
 		 * might find a suitable ScalarArrayOpExpr in the rel's joininfo list,
-		 * but it seems unlikely to be worth checking for.
+		 * but it seems unlikely to be worth expending the cycles to check.
+		 * And we definitely won't find a CurrentOfExpr here.  Hence, we don't
+		 * use TidQualFromRestrictInfo; but this must match that function
+		 * otherwise.
 		 */
-		if (!IsTidEqualClause(rinfo, rel))
+		if (rinfo->pseudoconstant ||
+			!restriction_is_securely_promotable(rinfo, rel) ||
+			!IsTidEqualClause(rinfo, rel))
 			continue;
 
 		/*


[parent: 60d99797bfb0]