From d17b6df239e6eebf288969e931cdbe8076d1fe12 Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Tue, 17 Feb 2015 22:33:38 +0200 Subject: [PATCH] Fix knn-GiST queue comparison function to return heap tuples first. The part of the comparison function that was supposed to keep heap tuples ahead of index items was backwards. It would not lead to incorrect results, but it is more efficient to return heap tuples first, before scanning more index pages, when both have the same distance. Alexander Korotkov --- src/backend/access/gist/gistscan.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/backend/access/gist/gistscan.c b/src/backend/access/gist/gistscan.c index cc8d818e11d..991858ff43f 100644 --- a/src/backend/access/gist/gistscan.c +++ b/src/backend/access/gist/gistscan.c @@ -41,9 +41,9 @@ pairingheap_GISTSearchItem_cmp(const pairingheap_node *a, const pairingheap_node /* Heap items go before inner pages, to ensure a depth-first search */ if (GISTSearchItemIsHeap(*sa) && !GISTSearchItemIsHeap(*sb)) - return -1; - if (!GISTSearchItemIsHeap(*sa) && GISTSearchItemIsHeap(*sb)) return 1; + if (!GISTSearchItemIsHeap(*sa) && GISTSearchItemIsHeap(*sb)) + return -1; return 0; }