RE: [PATCH] Keeps tracking the uniqueness with UniqueKey

Hi Andy,

A small thing I found:

+static List *
+get_exprs_from_uniqueindex(IndexOptInfo *unique_index,
+ List *const_exprs,
+ List *const_expr_opfamilies,
+ Bitmapset *used_varattrs,
+ bool *useful,
+ bool *multi_nullvals)
…
+ indexpr_item = list_head(unique_index->indexprs);
+ for(c = 0; c < unique_index->ncolumns; c++)
+ {

I believe the for loop must be over unique_index->nkeycolumns, rather than columns. It shouldn’t include the extra non-key columns. This can currently lead to invalid memory accesses as well a few lines later when it does an array access of unique_index->opfamily[c] – this array only has nkeycolumns entries.

-Floris

From: Andy Fan <zhihui(dot)fan1213(at)gmail(dot)com>
Sent: Sunday 19 July 2020 5:03 AM
To: Dmitry Dolgov <9erthalion6(at)gmail(dot)com>
Cc: David Rowley <dgrowleyml(at)gmail(dot)com>; PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>; Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>; Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>; rushabh(dot)lathia(at)gmail(dot)com
Subject: Re: [PATCH] Keeps tracking the uniqueness with UniqueKey [External]

Fixed a test case in v10.

--
Best Regards
Andy Fan