Re: Automatic optimization of IN clauses via INNER JOIN

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2009/12/18 Robert Haas <robertmhaas@xxxxxxxxx>:
> 2009/12/18 Grzegorz Jaśkiewicz <gryzman@xxxxxxxxx>:
>> On Fri, Dec 18, 2009 at 2:18 PM, Robert Haas <robertmhaas@xxxxxxxxx> wrote:
>>
>>> NOT IN is the only that really kills you as far as optimization is
>>> concerned.  IN can be transformed to a join.  NOT IN forces a NOT
>>> (subplan)-type plan, which bites - hard.
>>
>> in a well designed database (read: not abusing NULLs) - it can be done
>> with joins too.
>
> But not by PostgreSQL, or so I believe.

using left join ?



-- 
GJ

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