Re: Slow query with a lot of data

Am 21.08.2008 um 16:39 schrieb Scott Carey:

> It looks to me like the work_mem did have an effect.
>
> Your earlier queries had a sort followed by group aggregate at the
> top, and now its a hash-aggregate. So the query plan DID change.
> That is likely where the first 10x performance gain came from.

But it didn't change as I added the sub select.
Thank you guys very much. The speed is now ok and I hope I can finish
tihs work soon.

But there is another problem. If I run this query without the
limitation of the user id, postgres consumes about 150GB of disk space
and dies with

ERROR: could not write block 25305351 of temporary file: No space
left on device

After that the avaiable disk space is back to normal.

Is this normal? The resulting table (setup1) is not bigger than 1.5 GB.

moritz