On Thu, 30 Oct 2003 02:52:52 +0100 Brad Knowles <brad.knowles@skynet.be> wrote:

I think you could do full word indexing per message, and then store that index information in the database. Searching for phrases would require hitting the message bodies themselves, but searching for individual words could be done on indexed fields.

Consider an index which records not just the fact of a token's presence in an entity, but also the offsets at which it occurs within the entity. Searching for phrases then consists of searching for objects which satisfy the boolean "X AND Y", as well as the smaller clause "offset(X)

• length (X) + 1|2 == offset (Y)". Larger phrases extend the equivalence language linearly, tho they create exponential search costs.

-- J C Lawrence
---------(*) Satan, oscillate my metallic sonatas. claw@kanga.nu He lived as a devil, eh?
http://www.kanga.nu/~claw/ Evil is a name of a foeman, as I live.