Re: Table UPDATE is too slow

Ron St-Pierre <rstpierre(at)syscor(dot)com> writes:
> Does anyone have some idea on how we can increase speed, either by
> changing the updates, designing the database
> differently, etc, etc? This is currently a big problem for us.

> Other notables:
> The UPDATE is run from a within a function: FOR rec IN SELECT ...LOOP
> RETURN NEXT rec; UPDATE dataTable.....

One point that I don't think was made before: by doing a collection of
updates in this serial one-at-a-time fashion, you are precluding any
possibility of query optimization over the collection of updates. It
might win to dump the update data into a temp table and do a single
UPDATE command joining to the temp table. Or not --- quite possibly not
--- but I think it's something to think about.

regards, tom lane