Thread: pgsql: Defend against JOINs having more than 32K columns altogether.
pgsql: Defend against JOINs having more than 32K columns altogether.
From
tgl@postgresql.org (Tom Lane)
Date:
Log Message: ----------- Defend against JOINs having more than 32K columns altogether. We cannot currently support this because we must be able to build Vars referencing join columns, and varattno is only 16 bits wide. Perhaps this should be improved in future, but considering that it never came up before, I'm not sure the problem is worth much effort. Per bug #4070 from Marcello Ceschia. The problem seems largely academic in 8.0 and 7.4, because they have (different) O(N^2) performance issues with such wide joins, but back-patch all the way anyway. Tags: ---- REL8_2_STABLE Modified Files: -------------- pgsql/src/backend/parser: parse_relation.c (r1.125 -> r1.125.2.1) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/parse_relation.c?r1=1.125&r2=1.125.2.1) pgsql/src/include/access: attnum.h (r1.22 -> r1.22.2.1) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/access/attnum.h?r1=1.22&r2=1.22.2.1)