On Dec 11, 2008, at 3:37 AM, Angri wrote:
> > Here it is: http://www.sqlalchemy.org/trac/ticket/1244 > > Maybe it is good idea to drop some new lines in faq? Something like > this: > > Q: How should I extend sqlalchemy.schema.Column? > A: You surely dont need it. Recommended way to achive your possible > needs is to write instance-factory function which decorates creation > of sqlalchemy.schema.Column instances. > > Q: But I'm really need it! > A: Ok. To subclass Column, this is the current recipe: > > from sqlalchemy.sql.util import Annotated, annotated_classes > > class MyColumn(Column): > ... > > class AnnotatedMyColumn(Annotated, MyColumn): > pass > > annotated_classes[MyColumn] = AnnotatedMyColumn > > Do not forget to put AnnotatedMyColumn in the module namespace, or > your schema will not be pickleable! > > Correct me please if I am wrong somewhere and excuse me for my > English. Well the AnnotatedMyColumn part is less than ideal since its an internal. the way that works could very likely change. Creating an AnnotatedXXX class *can* be automated. the pickle thing just might be a caveat we'd document or arrange for an exception to occur (like putting a throw in a __getstate__ method). --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
