=?iso-8859-1?q?C=E9dric_Villemain?= <cedric(at)2ndquadrant(dot)com> writes:
>> I have noticed that with a SELECT query containing the following
>> column LIKE ?
>> and an index on that column, PostgreSQL will not use the index
>> even if the parameter doesn't contain special pattern characters
>> such as %.
> you should have a postgresql 8.3,isn't it ?
> like is equal to "=" in your case, since 8.4
No, the planner has understood about wildcard-free LIKE patterns
producing an "=" index condition at least since 7.3. I think what the
OP is complaining about is the problem that the pattern has to be
actually constant (ie, NOT a parameter) before it can be optimized into
an index condition. This should be better in 9.2 ...
regards, tom lane
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