Re: NOT LIKE much faster than LIKE?

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От Tom Lane
Тема Re: NOT LIKE much faster than LIKE?
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Msg-id 28232.1137014000@sss.pgh.pa.us
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Ответ на Re: NOT LIKE much faster than LIKE?  ("Jim C. Nasby" <jnasby@pervasive.com>)
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"Jim C. Nasby" <jnasby@pervasive.com> writes:
> On Wed, Jan 11, 2006 at 09:39:47PM +0100, Andrea Arcangeli wrote:
>> The index only helps the above query with = 0 and not the one with != 0,
>> but it seems not needed in practice.

> I suspect this is because of a lack of stats for functional indexes.

No, it's because != isn't an indexable operator.

            regards, tom lane

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