Sorry, google groups formatted that *really* poorly. On Jul 8, 12:28 pm, Mike Lewis <mikelikes...@gmail.com> wrote: > That's a fair point. > > I think one interface might be casting a FromClause into a WithClause > similar to how one would alias something. > > With postgres it seams like when going from a WITH to WITH recursive > is adding a UNION ALL and the recursive term. Throwing out an idea for > an interface (for postgres at least): > > Say you want to make > > WITH RECURSIVE included_parts(sub_part, part, quantity) AS ( > SELECT sub_part, part, quantity FROM parts WHERE part = > 'our_product' > UNION ALL > SELECT p.sub_part, p.part, p.quantity > FROM included_parts pr, parts p > WHERE p.part = pr.sub_part > ) > > First: > > included_parts = with_([parts.c.subpart, parts.c.part, > parts.c.quantity], whereclause=parts.c.part=='our_product') # could > also cast a SelectClause (or maybe even selectable) to a with_ by > using selectable.with_() > > included_parts would compile to "WITH include_parts AS (SELECT > sub_part, part, quantity FROM parts WHERE part = 'our_product')" > > then we do: > > included_parts = base.recursive( > [included_parts.c.sub_part, included_parts.c.part, > included_parts.c.quantity], > whereclause=included_parts.c.part==parts.c.part, > all=True) > > Which would compile to the desired with clause. > > then a select(included_parts.c.part) would give you: > > WITH RECURSIVE included_parts(sub_part, part, quantity) AS ( > SELECT sub_part, part, quantity FROM parts WHERE part = > 'our_product' > UNION ALL > SELECT p.sub_part, p.part, p.quantity > FROM included_parts pr, parts p > WHERE p.part = pr.sub_part > ) > SELECT included_parts.part, > > Where can I find information on the Oracle syntax and other ones you'd > like to support? > > On Jul 8, 11:46 am, Michael Bayer <mike...@zzzcomputing.com> wrote: > > > > > I'd really be interested in defining a system that covers WITH / RECURSIVE > > entirely, and makes sense both with PG / SQL server as well as Oracle. > > The work here is figuring out what is common about those two approaches and > > what an API that is meaningful for both would look like. Implementation > > and tests are just the grunt work here. > > > On Jul 8, 2010, at 2:03 PM, Mike Lewis wrote: > > > > I'd be interested in prototyping a WithClause or something similar if > > > you think it might be useful. > > > > I imagine it would have similar semantics to a FromClause but would be > > > prepended to the query. Currently, I'm not too interested in > > > prototyping the RECURSIVE part and only care about Postgres. > > > > For me to implement this would it be possible to do this in a non- > > > intrusive manner (outside of modifying core SA code?) I'd guess it > > > would have similar semantics to how select() will automatically > > > include FromClauses that for columns that reference them. > > > > Also, it would probably chain the WITHs automatically too. > > > > Any thoughts? > > > > Thanks, > > > Mike > > > > On Jul 6, 4:31 pm, Michael Bayer <mike...@zzzcomputing.com> wrote: > > >> this is the current status of that: > > > >>http://groups.google.com/group/sqlalchemy/browse_thread/thread/c20a4f... > > > >> WITHand OVER seem to be the upcoming things we'll have to work on (PG, > > >> MSSQL, DB2 supportWITH). Oracle makesWITHdifficult. Its also > > >> getting to be time to do a DB2 dialect. > > > >> On Jul 6, 2010, at 7:07 PM, Mike Lewis wrote: > > > >>> Does SA support this syntax? > > > >>>http://www.postgresql.org/docs/9.0/static/queries-with.html > > > >>> Thanks, > > >>> Mike > > > >>> -- > > >>> You received this message because you are subscribed to the Google > > >>> Groups "sqlalchemy" group. > > >>> To post to this group, send email to sqlalch...@googlegroups.com. > > >>> To unsubscribe from this group, send email to > > >>> sqlalchemy+unsubscr...@googlegroups.com. > > >>> For more options, visit this group > > >>> athttp://groups.google.com/group/sqlalchemy?hl=en. > > > > -- > > > You received this message because you are subscribed to the Google Groups > > > "sqlalchemy" group. > > > To post to this group, send email to sqlalch...@googlegroups.com. > > > To unsubscribe from this group, send email to > > > sqlalchemy+unsubscr...@googlegroups.com. > > > For more options, visit this group > > > athttp://groups.google.com/group/sqlalchemy?hl=en.
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