Re: One-Shot Plans

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Simon Riggs <simon@2ndQuadrant.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2011-06-14T20:36:06Z
Lists: pgsql-hackers
Simon Riggs <simon@2ndQuadrant.com> writes:
> Currently, the planner and executor are mostly independent of each
> other: the planner doesn't really know when the plan will be executed,
> and the executor doesn't know how recently the plan was made.

> We can work out the various paths through the traffic cop to see when
> a plan will be a "one-shot" - planned and then executed immediately,
> then discarded.

I have already got plans for a significantly more sophisticated approach
to this.

> In those cases we can take advantage of better optimisations. Most
> interestingly, we can evaluate stable functions at plan time, to allow
> us to handle partitioning and partial indexes better.

I don't believe that's correct in detail.

			regards, tom lane