Re: Performance problem from migrating between versions!

Thanks,

It worked. I have read in the docs what this "enable_hashagg" do, but I
couldn't understand it. What does it change?

 From the Doc:
-------
enable_hashagg (boolean)

    Enables or disables the query planner's use of hashed aggregation
    plan types. The default is on. This is used for debugging the query
    planner.

--------

How it is used to debug the query planner? And why it lower the mem usage?

Thank you in advance.

Kaloyan Iliev




Tom Lane wrote:

>Kaloyan Iliev Iliev <news1@faith.digsys.bg> writes:
>
>
>>I have the following problem. A week ago we've migrated from PGv7.2.3 to
>>7.4.6. There were a lot of things in the apps to chenge but we made
>>them. But one query doesn't want to run. In the old PGv7.2.3 it passes
>>for 10 min. In the new one it gaves:
>>DBD::Pg::st execute failed: ERROR:  out of memory
>>
>>
>
>Does setting enable_hashagg to OFF fix it?
>
>            regards, tom lane
>
>
>
>