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Re: Extended statistics for correlated columns, row estimates when values are not in MCVs list - Mailing list pgsql-general

From Michael Lewis
Subject Re: Extended statistics for correlated columns, row estimates when values are not in MCVs list
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Msg-id CAMcsB=wSWvVwkj4NyuKFvyyPK+v0w=an700qUgy2k1Sj7G1raA@mail.gmail.com
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In response to Re: Extended statistics for correlated columns, row estimates when values are not in MCVs list  (Tomas Vondra <tomas.vondra@enterprisedb.com>)
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On Mon, Dec 7, 2020 at 8:31 AM Tomas Vondra <tomas.vondra@enterprisedb.com> wrote:
What you might try is defining the statistics with only the functional
dependencies. That should consider the column-level correlation even
when the combination of values is not in the MCV. It might make the
"good" estimate worse, but that's an inherent trade-off.

Thanks very much. Removing MCVs type works perfectly for my use cases. 

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