[EMAIL PROTECTED] says...
> A partial index is a index on a subset of a table. The case I can think of > is a list of transactions, some of which are yet to be billed. They have a > BillID field which is NULL. since this is the recent set it is queried quite > often, so you can build an index like: > CREATE INDEX x ON table ( customerid ) WHERE billid IS NULL > Now an index can be used on customer when searching for only unbilled things > whereas normally it would also have to search for all historical things as > well. > So, you get the benefit of a smaller index that is more useful to boot. Hmmm... this is kinda like the Oracle thing where tables can be partitioned? Sort of? Paul... -- plinehan x__AT__x yahoo x__DOT__x com C++ Builder 5 SP1, Interbase 6.0.1.6 IBX 5.04 W2K Pro Please do not top-post. ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html