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

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

From
tgl@svr1.postgresql.org (Tom Lane)
Date:
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.

Modified Files:
--------------
    pgsql/src/backend/parser:
        parse_expr.c (r1.185 -> r1.186)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/parse_expr.c.diff?r1=1.185&r2=1.186)