Re: Redundant Unique plan node for table with a unique index

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От Andy Fan
Тема Re: Redundant Unique plan node for table with a unique index
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Msg-id CAKU4AWp60USTODSvve3-iQJ5um=SQLXJ95AvmdO9A6+qcS9LTA@mail.gmail.com
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Ответ на Re: Redundant Unique plan node for table with a unique index  (David Rowley <dgrowleyml@gmail.com>)
Ответы Re: Redundant Unique plan node for table with a unique index  (Damir Belyalov <dam.bel07@gmail.com>)
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I don't think this is a good way to do this.  The method you're using
only supports this optimisation when querying a table directly.  If
there were subqueries, joins, etc then it wouldn't work as there are
no unique indexes.  You should probably have a look at [1] to see
further details of an alternative method without the said limitations.

David

[1] https://postgr.es/m/flat/CAKU4AWqZvSyxroHkbpiHSCEAY2C41dG7VWs%3Dc188KKznSK_2Zg%40mail.gmail.com


The nullable tracking blocker probably has been removed by varnullingrels
so I will start working on UniqueKey stuff very soon, thank you David
for remember of this feature!

--
Best Regards
Andy Fan

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