Re: Adding foreign key performance

>>>>> "J" == Jeff <threshar(at)torgo(dot)978(dot)org> writes:

J> And this leads to the place we'd get a huge benefit: Restoring
J> backups.. If there were some way to bump up sort_mem while doing
J> the restore.. things would be much more pleasant. [Although, even

There was a rather substantial thread on this about the time when
7.4b1 was released.

J> better would be to disable FK stuff while restoring a backup and
J> assume the backup is "sane"] How we'd go about doing that is the
J> subject of much debate.

If you're restoring from a pg_dump -Fc (compressed dump) it already
happens for you. The indexes and foreign keys are not added until the
very end, from what I recall.

J> Perhaps add the functionality to pg_restore? ie, pg_restore -s
J> 256MB mybackup.db? It would just end up issuing a set
J> sort_mem=256000..

This was essentially my proposal, though I had better speed
enhancement by increasing the number of checkpoint buffers.

--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Vivek Khera, Ph.D. Khera Communications, Inc.
Internet: khera(at)kciLink(dot)com Rockville, MD +1-240-453-8497
AIM: vivekkhera Y!: vivek_khera http://www.khera.org/~vivek/