Re: Optimization- Check the set of conditionals on a WHERE clause against CHECK constraints.

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От Tom Lane
Тема Re: Optimization- Check the set of conditionals on a WHERE clause against CHECK constraints.
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Msg-id 23660.1454793123@sss.pgh.pa.us
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Ответ на Optimization- Check the set of conditionals on a WHERE clause against CHECK constraints.  (Shubham Barai <shubhambaraiss@gmail.com>)
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Shubham Barai <shubhambaraiss@gmail.com> writes:
> I was searching for project ideas and found this

> 1.Optimization- Check the set of conditionals on a WHERE clause against
> CHECK constraints  on the table being queried and remove any conditionals
> which *must* be true due to the CHECK constraints.

> Is it expensive for  simple queries?

> will it optimize  general queries ?

TBH, it sounds like it would almost always be a waste of planning cycles.
I doubt that typical applications would issue many queries in which such
an optimization would apply.
        regards, tom lane



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