you can pass a lambda as the value for a bindparam() and it will be called at compile time.
On Apr 1, 2010, at 6:34 PM, Kent Bower wrote: > Thanks for the info. > Still wondering, is there a way to tell the orm (a join criterion or a binary > expression) "use this function to find the param for the bind"? > > On Apr 1, 2010, at 6:11 PM, "Michael Bayer" <mike...@zzzcomputing.com> wrote: > >> Kent wrote: >>> I believe (correct me if you know better) that an line subquery is >>> quite a bit less efficient than a join. That was my motivation for >>> avoiding that because there are so many rows and we've already seen >>> performance problems with our queries... >> >> with a high quality planner, it should not be. in any case, you're >> looking for an aggregate value (the lowest). So without fetching many >> rows, a subquery is unavoidable, though you have a choice whether you'd >> like it correlated within the columns query (the normal way), or as an >> additional selectable in the FROM clause (avoids correlation). >> >>> >>> In the end I'd like the object to have a "saleprice" attribute (either >>> column_property or, if possible, association_proxy) that is the single >>> saleprice for the given date and store. >>> >>> When using the association proxy, can I somehow specify the first item >>> in the list? >> >> no, if you truly wanted to retrieve the full list of related items and >> display the price of the lowest, you'd use an ordinary method on your >> class to do that. >> >> -- >> 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 at >> http://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 at > http://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 at http://groups.google.com/group/sqlalchemy?hl=en.
