On Sat, Dec 20, 2003 at 04:14:51PM -0800, Jeff Davis wrote: > > > > > > What, exactly, is a partial index? A functional index is an index on > > > something like ((ColumnX*2)/14)? I think the functional one (is that > > > also an expression index?) is on the way. > > > > 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: > > > > Are NULLs even indexed?
No, but with a partial index you can acheive the same effect. -- Martijn van Oosterhout <[EMAIL PROTECTED]> http://svana.org/kleptog/ > (... have gone from d-i being barely usable even by its developers > anywhere, to being about 20% done. Sweet. And the last 80% usually takes > 20% of the time, too, right?) -- Anthony Towns, debian-devel-announce
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