pgsql: Fix performance issue in exprTypmod(): for a COALESCE expression,

From: tgl(at)svr1(dot)postgresql(dot)org (Tom Lane)
To: pgsql-committers(at)postgresql(dot)org
Subject: pgsql: Fix performance issue in exprTypmod(): for a COALESCE expression,
Date: 2005-11-18 23:08:13
Message-ID: 20051118230813.6993FDBB31@svr1.postgresql.org
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Log Message:
-----------
Fix performance issue in exprTypmod(): for a COALESCE expression, it
recursed twice on its first argument, leading to exponential time spent
on a deep nest of COALESCEs ... such as a deeply nested FULL JOIN would
produce. Per report from Matt Carter.

Tags:
----
REL8_1_STABLE

Modified Files:
--------------
pgsql/src/backend/parser:
parse_expr.c (r1.185 -> r1.185.2.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/parse_expr.c.diff?r1=1.185&r2=1.185.2.1)

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