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Re: [PERFORM] Estimation problem with a LIKE clause containing a / - Mailing list pgsql-hackers

From Tom Lane
Subject Re: [PERFORM] Estimation problem with a LIKE clause containing a /
Date
Msg-id 11342.1194626025@sss.pgh.pa.us
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In response to Re: [PERFORM] Estimation problem with a LIKE clause containing a /  (Gregory Stark <stark@enterprisedb.com>)
Responses Re: [PERFORM] Estimation problem with a LIKE clause containing a /
Re: [PERFORM] Estimation problem with a LIKE clause containing a /
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Gregory Stark <stark@enterprisedb.com> writes:
> Could we not use the bogus range to calculate the histogram estimate
> but apply the LIKE pattern directly to the most-frequent-values
> instead of applying the bogus range? Or would that be too much code
> re-organization for now?

We have already done that for quite some time.  It won't help
Guillaume's case anyhow: he's got no MCVs, presumably because the field
is unique.

            regards, tom lane

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