Re: Re: Does PostgreSQL support EXISTS? - Mailing list pgsql-general

>     | On postgres at least, exists is faster than in.
>     |
>     | They are equivalent though.
>     |
>     | select x from a where v in (select v from b)
>     | select x from a where exists (select 1 from b where a.v = b.v)
>     | select x from a, b where a.v = b.v
>     |
>     | are all the same. Postgres doesn't quite know that yet though.
>
>
> If you do an EXPLAIN on Oracle with the first 2 queries above, you will
> notice that the second one is faster in Oracle too (i.e., EXISTS is faster
> than IN).

So it is confirmed.  Interesting.

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