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.
