pgsql: Fix patternsel() and callers to do the right thing for NOT LIKE - Mailing list pgsql-committers

From tgl@postgresql.org (Tom Lane)
Subject pgsql: Fix patternsel() and callers to do the right thing for NOT LIKE
Date
Msg-id 20071107210037.8FBB9754229@cvs.postgresql.org
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Log Message:
-----------
Fix patternsel() and callers to do the right thing for NOT LIKE and the other
negated-match operators.  patternsel had been using the supplied operator as
though it were a positive-match operator, and thus obtaining a wrong result,
which was even more wrong after the caller subtracted it from 1.  Seems
cleanest to give patternsel an explicit "negate" argument so that it knows
what's going on.  Also install the same factorization scheme for pattern
join selectivity estimators; even though they are just stubs at the
moment, this may keep someone from making the same type of mistake when
they get filled out.  Per report from Greg Mullane.

Backpatch to 8.2 --- previous releases do not show the problem because
patternsel() doesn't actually use the operator directly.

Modified Files:
--------------
    pgsql/src/backend/utils/adt:
        selfuncs.c (r1.236 -> r1.237)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/selfuncs.c?r1=1.236&r2=1.237)

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