Re: IN surpasses NOT EXISTS in 7.4RC2 ?? - Mailing list pgsql-performance

Rajesh Kumar Mallah wrote:
>
> Hi,
>
> NOT EXISTS is taking almost double time than NOT IN .
> I know IN has been optimised in 7.4 but is anything
> wrong with the NOT EXISTS?
>
> I have vaccumed , analyze and run the query many times
> still not in is faster than exists :>

Seems fine.  In 7.4, NOT IN will often be faster that NOT EXISTS.  NOT
EXISTS didn't change --- there are restrictions on how far we can
optimize NOT EXISTS.  NOT IN has just become much faster in 7.4.

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