Re: Utilizing multiple cores for one query

On Dec 1, 2007 8:21 AM, henk de wit <henk53602(at)hotmail(dot)com> wrote:
> I wonder whether the current versions of postgres (i.e. either 8.2 or 8.3)
> are able to utilize multiple cores for the execution of a single query?

Nope.

> This is one thing that systems like SQL Server and Oracle have been able to
> do for quite some time. I haven't seen much in the documentation that hints
> that this may be possible in PG, nor did I find much in the mailinglists
> about this. The only thing I found was a topic that discussed some patches
> that may eventually lead to a sequence scan being handled by multiple cores.

I believe the threads you're talking about were related to scanning,
not parallel query. Though, when Qingqing and I were discussing
parallel query a little over a year ago, I do seem to recall several
uninformed opinions stating that sequential scans were the only thing
it could be useful for.

> Could someone shed some light on the current or future abilities of PG for
> making use of multiple cores to execute a single query?

Currently, the only way to parallelize a query in Postgres is to use pgpool-II.

http://pgpool.projects.postgresql.org/

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