[sqlalchemy] Re: Generative queries in SA0.3 ?
exhuma.twn ha scritto: I have seen that in SA 0.4 on can do something like: q = table.select() q = q.where(x=1) q = q.where(z=2) ... Is this also possible in SA 0.3? I want to build a web-page where a user can refine filters on the go, to perform a drill-down in a data set. Doing this with plain-text SQL is fairly easy, but doing it with SA is not as straight-forward. Considering this scenario, would it be possible to *remove* one such filter from a query? Say, remove the x=1 from the above query. You must post-pone rendering of qry where clause... where_clause = [] where_clause.append( cond1 ) where_clause.append( cond2 ) where_clause.append( cond3 ) you can at this point of programm remove some condition positinally or by content. where_clause.pop( cond2) or del where_clause[1] finally you can rendere your qry: your_base_qry = session.query( bla bla ) if where_clause: your_removed_qry = your_base_qry.filter( and_( *where_clause ) ) Glauco -- ++ Glauco Uri - Programmatore glauco(at)allevatori.com Sfera Carta Software® [EMAIL PROTECTED] Via Bazzanese,69 Casalecchio di Reno(BO) - Tel. 051591054 ++ --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups sqlalchemy group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Generative queries in SA0.3 ?
On Nov 19, 12:41 pm, Glauco [EMAIL PROTECTED] wrote: exhuma.twn ha scritto: I have seen that in SA 0.4 on can do something like: q = table.select() q = q.where(x=1) q = q.where(z=2) ... Is this also possible in SA 0.3? I want to build a web-page where a user can refine filters on the go, to perform a drill-down in a data set. Doing this with plain-text SQL is fairly easy, but doing it with SA is not as straight-forward. Considering this scenario, would it be possible to *remove* one such filter from a query? Say, remove the x=1 from the above query. You must post-pone rendering of qry where clause... where_clause = [] where_clause.append( cond1 ) where_clause.append( cond2 ) where_clause.append( cond3 ) you can at this point of programm remove some condition positinally or by content. where_clause.pop( cond2) or del where_clause[1] finally you can rendere your qry: your_base_qry = session.query( bla bla ) if where_clause: your_removed_qry = your_base_qry.filter( and_( *where_clause ) ) Glauco Thanks. This is nearly the way I am doing it right now. I didn't know and_ could take a list. This is will simplify things. I suppose I will stick to this method then as removing refining filters (adding and removing) is something that is done quite often. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups sqlalchemy group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Generative queries in SA0.3 ?
On Nov 18, 2007, at 11:26 AM, exhuma.twn wrote: I have seen that in SA 0.4 on can do something like: q = table.select() q = q.where(x=1) q = q.where(z=2) ... Is this also possible in SA 0.3? 0.3. can build up selects by using methods such as append_whereclause(). but in 0.3 its not generative, you modify the current select object in place and the append_() methods have no return value. Considering this scenario, would it be possible to *remove* one such filter from a query? Say, remove the x=1 from the above query. neither 0.3 or 0.4 can do that, and this is basically because you don't need to.in 0.4 just hold onto the previous select() which doesn't have the filter. If you're building from a web form, you'd be translating form state into a newly built select() each time so i dont see any use case for removing components there. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups sqlalchemy group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
