Re: SELECT DISTINCT chooses parallel seqscan instead of indexscan on huge table with 1000 partitions

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От David Rowley
Тема Re: SELECT DISTINCT chooses parallel seqscan instead of indexscan on huge table with 1000 partitions
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Msg-id CAApHDvqWfGdUpTUp9s7AZYSeh44aLEXoBQS7UcfKM0zKhTCkiQ@mail.gmail.com
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Ответ на Re: SELECT DISTINCT chooses parallel seqscan instead of indexscan on huge table with 1000 partitions  (Tom Lane <tgl@sss.pgh.pa.us>)
Ответы Re: SELECT DISTINCT chooses parallel seqscan instead of indexscan on huge table with 1000 partitions
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On Sat, 11 May 2024 at 13:33, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> I do kind of wonder why it's producing both a hashagg and a Unique
> step --- seems like it should do one or the other.

It still needs to make the duplicate groups from parallel workers unique.

David

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