Hi Micheal, makes sense - i've implemented it and so far so good.
Some details, if it might help: *I inject the session created in the different apps (w1, w2 or w3) into the "models_app" *The base class (1 unique base class used by all models) is created in the "models app". Thanks, On May 20, 5:41 am, Michael Bayer <mike...@zzzcomputing.com> wrote: > On May 19, 2011, at 11:06 AM, 371c wrote: > > > > > Hi all, > > > Scenario: i have a couple of models that i'd like to reuse across 3 > > different web apps (w1, w2, w3). > > > The idea is to: > > > * create a separate project (eg. models_app) to be installed into the > > python env via "python setup install" - sort of like a shared library. > > > * In w1, w2 and/or w3, import "models_app" to have access to the > > shared models. > > > I have no idea of what could be the dangers of doing this especially > > in respect to sqla (scoped?) sessions, transactions and the like.. > > > Any thoughts, alternatives? > > The model, that is your classes, mappers, and Table objects (lets call it the > class-level structure), represent a fixed structure that represent a schema > that may exist in any arbitrary database; the instantiation of that model, > i.e. individual object instances, then represent the data within a specific > database. The class-level structure isn't linked to an actual database. > The Session on the other hand represents a handle to an active transaction in > a database - it then maintains individual object instances, which by their > association with the Session, are extensions of the Session's state which is > ultimately an in-memory representation of a remote transaction. > > So sharing the model among different applications, that is, the class-level > structure doesn't really have any impact on anything, its only the Session as > well as the *instances* of your model classes, attached to that Session, that > have some association with a particular database. -- 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.
