Jean-Luc Lachance wrote: > > BULL. > > How many times does PG have to scan the whole table because of MVCC? > At least with partitioning there is a fighting chance that that won't be > necessary. > Queries that involve the field on which the table is partitioned execute > faster by an order of magnitude. > It also helps with vaccuming as PG can vaccum only one partition at a > time. > I have 17M row table where all records get frequently updated over a > year. > I would do my own partitioning with inheritance if it was not broken. > Partitioning would be a BIG plus in my book. So would visibility of > records but that is another fight.
I meant to say visibility of record in the index. > > JLL > > Vivek Khera wrote: > > > > >>>>> "JB" == Jeff Boes <[EMAIL PROTECTED]> writes: > > > > JB> Will a query against a table of 0.5 million rows beat a query against > > JB> a table of 7 million rows by a margin that makes it worth the hassle > > JB> of supporting 15 "extra" tables? > > > > I think you'll be better off with a single table, as you won't have > > contention for the index pages in the cache. > > > > One thing to do is to reindex reasonably often (for PG < 7.4) to avoid > > index bloat, which will make them not fit in cache. Just check the > > size of your index in the pg_class table, and when it gets big, > > reindex (assuming you do lots of updates/inserts to the table). > > > > Your table splitting solution sounds like something I'd do if I were > > forced to use mysql ;-) > > > > -- > > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= > > Vivek Khera, Ph.D. Khera Communications, Inc. > > Internet: [EMAIL PROTECTED] Rockville, MD +1-240-453-8497 > > AIM: vivekkhera Y!: vivek_khera http://www.khera.org/~vivek/ > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 9: the planner will ignore your desire to choose an index scan if your > > joining column's datatypes do not match > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
