On Dec 4, 2012, at 4:32 PM, Diego Woitasen wrote: > > > > > > > > I'm mixing ORM and Core in my app because I performance in critical in some > parts of the code. Are there other problems related to this mix?
I wouldn't call them "problems", but to the degree that you're using plain Core functions you just won't get ORM awareness of that. If for example you emitted a bunch of INSERT, UPDATE, DELETE statements, the objects loaded into your ORM session wouldn't be aware of those changes until a refresh. I'd also say it's not a given that the ORM needs to be bypassed for "performance critical" features, the performance issue of the ORM Query object is that loading rows into full fledged Python objects is a slow process. So if you need to run a query and get non-object results back, Query can run against individual columns, and you'll get SELECT performance that's more or less the same as you get from using Core directly, i.e.: session.query(MyClass.x, MyClass.y).... the Query has a little more overhead in constructing the underlying select() construct than doing it directly, so I guess it depends on what specific performance issues you were seeing. -- 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.
