Re: Support Parallel Query Execution in Executor

On 4/9/06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> That's not remotely the same thing: a backend is a very different animal
> from a bgwriter.

Yes, I know.  Had I known it would've been picked apart, I would've
described it better.

> In particular, bgwriter (and bgreaders if we had 'em)
> aren't database-specific, don't need to think about permission checking
> as they don't execute on behalf of particular users, don't have syscaches
> to keep in-sync with everything else, etc etc.

In the current proof-of-concept, there is a backend (manager) and
several reader-like processes; However, in this case, the readers
perform actual execution on behalf of the user.

The reader-like processes or "execution agents", whatever you want to
call them, are limited to the postgres database only because they've
been coded that way... but there's nothing that actually restricts
them from being used for any database.

--
Jonah H. Harris, Database Internals Architect
EnterpriseDB Corporation
732.331.1324