pgsql: Do not allow Unique nodes to be scanned backwards.

From: tgl(at)postgresql(dot)org (Tom Lane)
To: pgsql-committers(at)postgresql(dot)org
Subject: pgsql: Do not allow Unique nodes to be scanned backwards.
Date: 2008-08-05 21:29:01
Message-ID: 20080805212901.25027755315@cvs.postgresql.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-committers

Log Message:
-----------
Do not allow Unique nodes to be scanned backwards. The code claimed that it
would work, but in fact it didn't return the same rows when moving backwards
as when moving forwards. This would have no visible effect in a DISTINCT
query (at least assuming the column datatypes use a strong definition of
equality), but it gave entirely wrong answers for DISTINCT ON queries.

Tags:
----
REL7_4_STABLE

Modified Files:
--------------
pgsql/src/backend/executor:
execAmi.c (r1.75.4.2 -> r1.75.4.3)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/executor/execAmi.c?r1=1.75.4.2&r2=1.75.4.3)

Browse pgsql-committers by date

  From Date Subject
Next Message User Mkz 2008-08-06 06:31:43 pgbouncer - pgbouncer: asynctest: check if result comes back ok
Previous Message Tom Lane 2008-08-05 21:28:54 pgsql: Do not allow Unique nodes to be scanned backwards.