See the email about bitmapped indexes linked to from the TODO list item on bitmaps. Bitmap indexes allow arbitrary indexes to be combined into a single index. Btree indexes can not be combined.
--------------------------------------------------------------------------- Rajesh Kumar Mallah. wrote: > Hi, > > I have learnt from certain texts that bitmap indexes are very useful for > large DSS (decesion support systems). > > bitmap indexes are currently not available in postgresql. > > My question is in what way is a normal btree index in pgsql > inferior to bitmap indexes (found in oracle for example). > > is it just in terms of space requirements for performance too? > > > regds > mallah. > > > -- > Rajesh Kumar Mallah, > Project Manager (Development) > Infocom Network Limited, New Delhi > phone: +91(11)6152172 (221) (L) ,9811255597 (M) > > Visit http://www.trade-india.com , > India's Leading B2B eMarketplace. > > > > ---------------------------(end of broadcast)--------------------------- > TIP 2: you can get off all lists at once with the unregister command > (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED]) > -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073 ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
