From 94f565dcf1ada1f2a7c6905f205e14060c4ce08b Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 7 Feb 2013 18:22:19 -0500 Subject: [PATCH] Fix erroneous range-union logic for varlena types in contrib/btree_gist. gbt_var_bin_union() failed to do the right thing when the existing range needed to be widened at both ends rather than just one end. This could result in an invalid index in which keys that are present would not be found by searches, because the searches would not think they need to descend to the relevant leaf pages. This error affected all the varlena datatypes supported by btree_gist (text, bytea, bit, numeric). Per investigation of a trouble report from Tomas Vondra. (There is also an issue in gbt_var_penalty(), but that should only result in inefficiency not wrong answers. I'm committing this separately so that we have a git state in which it can be tested that bad penalty results don't produce invalid indexes.) Back-patch to all supported branches. --- contrib/btree_gist/btree_utils_var.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/contrib/btree_gist/btree_utils_var.c b/contrib/btree_gist/btree_utils_var.c index 9f8a132775b..691b10388ed 100644 --- a/contrib/btree_gist/btree_utils_var.c +++ b/contrib/btree_gist/btree_utils_var.c @@ -225,13 +225,13 @@ void gbt_var_bin_union(Datum *u, GBT_VARKEY *e, Oid collation, const gbtree_vinfo *tinfo) { - GBT_VARKEY *nk = NULL; - GBT_VARKEY *tmp = NULL; - GBT_VARKEY_R nr; GBT_VARKEY_R eo = gbt_var_key_readable(e); + GBT_VARKEY_R nr; if (eo.lower == eo.upper) /* leaf */ { + GBT_VARKEY *tmp; + tmp = gbt_var_leaf2node(e, tinfo); if (tmp != e) eo = gbt_var_key_readable(tmp); @@ -239,25 +239,26 @@ gbt_var_bin_union(Datum *u, GBT_VARKEY *e, Oid collation, if (DatumGetPointer(*u)) { - GBT_VARKEY_R ro = gbt_var_key_readable((GBT_VARKEY *) DatumGetPointer(*u)); + bool update = false; + + nr.lower = ro.lower; + nr.upper = ro.upper; if ((*tinfo->f_cmp) (ro.lower, eo.lower, collation) > 0) { nr.lower = eo.lower; - nr.upper = ro.upper; - nk = gbt_var_key_copy(&nr, TRUE); + update = true; } if ((*tinfo->f_cmp) (ro.upper, eo.upper, collation) < 0) { nr.upper = eo.upper; - nr.lower = ro.lower; - nk = gbt_var_key_copy(&nr, TRUE); + update = true; } - if (nk) - *u = PointerGetDatum(nk); + if (update) + *u = PointerGetDatum(gbt_var_key_copy(&nr, TRUE)); } else { -- 2.30.2