On Oct 2, 2008, at 4:05 PM, [EMAIL PROTECTED] wrote:
> > On Thursday 02 October 2008 22:26:06 Michael Bayer wrote: >> On Oct 2, 2008, at 11:57 AM, [EMAIL PROTECTED] wrote: >>> hi >>> lets say, A points to B. >>> i do a query against A about which things link to some instance >>> of B. then, >>> 1) if i specify eagerload, i get many times same object-data >>> being piped from the server; ok but i dont want it >>> 2) if i dont specify eagerload (lazy), access to each A fires a >>> lazyload-query for the (same) B! Although the object is in memory >>> already. is this expected behaviour or? the relevant dbid is >>> already present, hence it can be checked against session-caches >>> etc?? what should i do here? >> >> if you load an A that wasnt previously present, its A.bs collection >> is empty. >> The individual B objects might be in the session but the >> information that they are associated with your "A" is not present, >> unless we scanned through the Session and matched up foreign keys. >> This latter approach basically turns Session into its own >> relational engine which is why we dont even try to get into that. >> So the lazy query for the"B"s proceeds, but we do reuse the B's >> already present in the session so there is far less overhead >> associated with fetching the rows. >> >> The approach taken by some ORMs Ive seen is to link the A.bs load >> to load the .bs for *all* As. That seems pretty "dirty" to me >> since it means we have to keep track of Queries and such. > > nah, it's a simple *toone singular reference, not a collection. > can't something be done for it? hack something somewhere? a simple many-to-one will use query.get(x) for the lazyload, and no SQL will be issued if B is already present in the session. --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
