On 17.08.2010 12:16, Robert Collins wrote: > On Tue, Aug 17, 2010 at 10:12 PM, Abel Deuring > <[email protected]> wrote: >> On 17.08.2010 11:45, Robert Collins wrote: >>> So there is some conflation/confusion here I think. >>> >>> *subscribing* to a ft search - +1 >>> >>> putting a tsearch vector in the *subscription* - I'm lost why that is >>> useful. >> >> It's not a tsearch vector but a tsquery I want to store :) >> >> If you have a number of subscriptions to a full text search -- how else >> would you remove the not matching searches in something like >> >> SELECT whatever FROM bugsubscription >> WHERE bugsubscription.bug=our_current_bug_id >> AND there_is_a_match( >> (SELECT full_text FROM bug WHERE id=our_current_bug_id), >> bugsubscription.fulltext_search_words) >> >> With a canned tsquery you can use an WHERE expression like >> >> bugsubscription.tsquery @@ bug.fti > > I'd _really_ like to see a performance test of that; if it behaves > like some of the ts2 stuff we may be very disappointed.
Admittedly, I don't expect such a query to be very fast. But remember: We are not talking about web requests but about a script (or a job) that should generate emails not-too-long after a bug has been filed, somebody had commented on a bug, after bug status changes etc. I am all for using/writing efficient code, and if we get millions of subscriptions, performance is indeed an issue -- but if a script runs 10 or 30 seconds for a few hundred or thousand subscriptions, does not really matter, I think. (The same applies, BTW, for filtering on Python level.) Abel > > Long term we'll need an answer for out-of-db search though, when we > drop bug.fti (which I'm pretty confident will be the right thing to > do: ts2 has significant limitations and no sign of workarounds). > >> The other option I see would be to return all possible subscriptions in >> the SELECT and implement the fulltext filtering in Python -- but you >> didn't like that ;) > > I think it would scale poorly, yes. > > -Rob > _______________________________________________ Mailing list: https://launchpad.net/~launchpad-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~launchpad-dev More help : https://help.launchpad.net/ListHelp
