On Sep 8, 2014, at 3:14 PM, alchemy1 <veerukrish...@hotmail.com> wrote:
> In one of the YouTube videos on SQLAlchemy Mike said that some of the large > users of SQLAlchemy prefer to use plain SQLAlchemy instead of SQLAlchemy ORM. > What are the reasons behind that? the Core by itself is much much faster than the ORM in terms of fetching rows and being able to emit INSERT/UPDATE/DELETE directly with a lot less Python overhead. Using the Core also corresponds to SQL execution patterns in a 1-1 fashion. With the ORM, you can construct SELECTs as directly as you can with the Core, but for persistence, the flush() process is a lot more indirect. If your app doesn't have a data model that is very object oriented then the ORM might get in the way more than it helps. > I'm wondering because I started off with ORM and though I like it I've been > wondering whether I might be better off going with plain SQLAlchemy and > foregoing the ORM. > > What exactly would I lose if I give up the ORM that I may not realize right > now? > > What kinds of web applications (written in Pyramid in this case) are better > suited to use or not use ORM? IMHO I'd always use the ORM because I always write a traditional object model around my data. I drop into Core only if I'm really trying to skip some process in the ORM that I know is expensive, however the whole direction of the ORM especially in 1.0 is to allow better ORM-level workarounds for these things. this isn't merged yet, but you can take a peek at the performance profiling stuff I'm doing right now in the branch at https://bitbucket.org/zzzeek/sqlalchemy/src/fa7c8f88113d2e769274dee4aa4247b9c9aadec8/examples/performance/__init__.py?at=ticket_3100. -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
