Re: [HACKERS] pg_stat_statements query normalization, and the 'in' operator

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От Tom Lane
Тема Re: [HACKERS] pg_stat_statements query normalization, and the 'in' operator
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Msg-id 17373.1502551895@sss.pgh.pa.us
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Ответ на [HACKERS] pg_stat_statements query normalization, and the 'in' operator  (unixway.drive@gmail.com)
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unixway.drive@gmail.com writes:
> Given the following list of queries:

>    create table foo (id serial, bar integer);
>    select * from foo where id in (1);
>    select * from foo where id in (2,3);
>    select * from foo where id in (1,3,5);
>    select * from foo where id in (select id from foo);

> would it be possible to have first three select queries to be normalized 
> into a single one so that 'select query from pg_stat_statements' returns 
> something like:

>    select * from foo where id in (...);
>    select * from foo where id in (select id from foo);

Wouldn't recommend holding your breath for that.  But you could do the
same conversion on the client side that the parser would do anyway:

select * from foo where id = any ('{1,3,5}'::integer[]);
        regards, tom lane



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