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Re: BUG #17540: Prepared statement: PG switches to a generic query plan which is consistently much slower - Mailing list pgsql-bugs

From David Rowley
Subject Re: BUG #17540: Prepared statement: PG switches to a generic query plan which is consistently much slower
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Msg-id CAApHDvr+70jEZpraMZ8sj=UH77dBzCaeUc9EcJHB3YaxX9syNg@mail.gmail.com
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In response to Re: BUG #17540: Prepared statement: PG switches to a generic query plan which is consistently much slower  (Richard Guo <guofenglinux@gmail.com>)
Responses Re: BUG #17540: Prepared statement: PG switches to a generic query plan which is consistently much slower  (Richard Guo <guofenglinux@gmail.com>)
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On Fri, 7 Jul 2023 at 19:03, Richard Guo <guofenglinux@gmail.com> wrote:
> Attached is what I have in mind.  The patch extends the logic from two
> points.
>
> * it also checks OR clauses to see if it is always true.
>
> * it also checks for join clauses by additionally testing if the nulling
> bitmap is empty.

Do you mind writing some regression tests for this?

I don't really see an existing test file that would suit, maybe it's
worth adding something like predicate.sql

David

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