Andrew Schetinin wrote:
Hi Alex,

Thank you. I played with subqueries, but in this case I did not see a good enough improvement.

In my specific case, what I've seen from the query execution plans, is that without LIMIT the query uses Hash Joins, but once I add LIMIT, it starts using Nested Loop Joins almost everywhere.

Regards,

Andrew

On Wed, Feb 1, 2012 at 9:42 PM, Alex Lai <a...@sesda2.com <mailto:a...@sesda2.com>> wrote:

    Hi Andrew,
    I posted for another post, its may give you a workaround.
    I still not fully understand how PG choose execute plan that slow
    down so much.

    I had the same situation in one of my query.
    Use the subquery can speed up almost by 100 times faster.

    ..........

    Hope this help.


    Best Regards,
    Alex Lai

-- Best regards,


    Alex Lai
    OMI SIPS DBA ADNET Systems , Inc. 7515 Mission Drive, Suite A100
    Lanham, MD 20706 301-352-4657 (phone) 301-352-0437 (fax)
    a...@sesda2.com <mailto:a...@sesda2.com>




--
--
Andrew Schetinin
Hi Andrew,

I am interested in see your query.

--
Best regards,


Alex Lai
OMI SIPS DBA ADNET Systems , Inc. 7515 Mission Drive, Suite A100 Lanham, MD 20706 301-352-4657 (phone) 301-352-0437 (fax) a...@sesda2.com


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