Thanks! It seems so much more intuitive after seeing an example.
On Friday, July 8, 2016 at 11:51:49 AM UTC-4, Mike Bayer wrote: > > > > the basic idea (assuming ORM style) would be like: > > e = aliased(Engagement) > ee = aliased(Engagement) > > e1 = exists().where(and_( > ee.id == 156, > ee.target_id == e.target_id, > ee.candidate_id == e.candidate_id > )) > > e2 = exists().where(and_( > Message.id == e.id, > e1 > )) > > q = session.query(Message).filter(e2) > > > if that needs help with the correlation then we'd add some correlate() > calls, but it shouldn't, since the FROM nesting here is clear. > On 07/08/2016 03:21 AM, Tim Chen wrote: > > Hi, I'm wondering what the correct syntax is for a nested correlated > > exists subquery? > > > > I have Message and Engagement declarative tables and here is the query > > i'm trying to replicate: > > > > | > > select * > > from message m > > where exists ( > > select 1 from engagement e > > where m.engagement_id = e.id > > and exists ( > > select 1 from engagement ee > > where ee.id = 156 > > and ee.target_id = e.target_id > > and ee.candidate_id = e.candidate_id > > ) > > ); > > | > > > > Much appreciated! > > > > -tim > > > > -- > > You received this message because you are subscribed to the Google > > Groups "sqlalchemy" group. > > To unsubscribe from this group and stop receiving emails from it, send > > an email to sqlalchemy+...@googlegroups.com <javascript:> > > <mailto:sqlalchemy+unsubscr...@googlegroups.com <javascript:>>. > > To post to this group, send email to sqlal...@googlegroups.com > <javascript:> > > <mailto:sqlal...@googlegroups.com <javascript:>>. > > Visit this group at https://groups.google.com/group/sqlalchemy. > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
