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Re: extended statistics n-distinct on multiple columns not used when join two tables - Mailing list pgsql-performance

From Pavel Stehule
Subject Re: extended statistics n-distinct on multiple columns not used when join two tables
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Msg-id CAFj8pRCNu82ZCb4tMg9sCrZSqiLob84zfv+y38M1F7XaJEJFZA@mail.gmail.com
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In response to extended statistics n-distinct on multiple columns not used when join two tables  ("James Pang (chaolpan)" <chaolpan@cisco.com>)
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Hi

út 13. 6. 2023 v 11:21 odesílatel James Pang (chaolpan) <chaolpan@cisco.com> napsal:

Hi,

     When join two table on multiple columns equaljoin, rows estimation always use selectivity = multiplied by distinct multiple individual columns, possible to use  extended n-distinct statistics on multiple columns?

    PG v14.8-1, attached please check test case with details.


There is not any support for multi tables statistic

Regards

Pavel
 

 

Thanks,

 

James

      

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