Did you try something like this? q1=session.query(P1.userid, P1.extra, P1.title, P1.body) q2=session.query(P2.userid, "'X'", P2.title, P2.body) q3=session.query(P3.userid, "'X'", P3.title, P3.body)
q=q1.union_all(q2).union_all(q3) -- Mike Conley On Wed, Aug 26, 2009 at 10:45 PM, Seth <seedifferen...@gmail.com> wrote: > > I have three different types of post tables with all of the same > columns except that the first table has an extra column named > "type" (placed in-between the 'user_id' and 'title' columns of the > other tables). I want to do a UNION ALL that will combine the data > from all these tables into a single list (with a blank value for the > tables missing the "type" column), and then I want to sort the posts > by creation date. > > However, try as I might, I cannot seem to get this to work without > throwing me an ArgumentError of "All selectables passed to > CompoundSelect must have identical numbers of columns; select #1 has 7 > columns, select #2 has 6". I suspect this has something to do with > SQLAlchemy auto-magically reading the DeclarativeBase table classes. > > > The SQL version of this query would look something like: > > SELECT 'cat1' as category, * FROM posts_1 UNION ALL SELECT 'cat2', id, > user_id, 'NONE', title, body, created, updated FROM posts_2 UNION ALL > SELECT 'cat3', id, user_id, 'NONE', title, body, created, updated > FROM posts3 ORDER BY created DESC LIMIT 10 > > How can I get this to translate into SQLAlchemy with the extra 'NONE' > for the tables that don't have a "type" column without giving me the > ArgumentError? > > Thanks, > Seth > > > --~--~---------~--~----~------------~-------~--~----~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
