On Friday 24 August 2007 19:20:00 Gaetan de Menten wrote: > You might be interested by: http://techspot.zzzeek.org/?p=13 > (also in the examples directory of SQLAlchemy) > > On 8/24/07, praddy <[EMAIL PROTECTED]> wrote: > > ########################################################## > > from sqlalchemy import * > > meta = BoundMetaData('sqlite://', echo=False) > > > > # Parents table. > > parents = Table('parents', meta, > > Column("id", Integer, primary_key=True), > > Column("data", String(50), nullable=False) > > ) > > > > # Children_1 Table. > > children_1 = Table('children_1', meta, > > Column("id", Integer, primary_key=True), > > Column("data", String(50), nullable=False) > > ) > > > > # Children_2 Table. > > children_2 = Table('children_2', meta, > > Column("id", Integer, primary_key=True), > > Column("data", String(50)) > > ) > > > > # Association Table. > > # This is a generic table which can relate anything to parent. > > assoc = Table('assoc', meta, > > # parents.c.id > > Column("parent_id", Integer, ForeignKey(parents.c.id)), > > # associate's id either children_1.c.id or children_2.c.id or any > > other child. > > Column("assoc_id", Integer), > > # Which can be either 'child_1' or 'child_2' for now (can be used > > for extending children > > # type, decides which table to look in. > > Column("assoc_type", String(20)) > > ) > > ####################################################### > > > > I am a novice with respect to sqlalchemy & may be RDBMS as well. > > How would you like to work on this scenario to achieve backwards > > cascading (may not be the right word) which means when one deletes > > one specific child from children_1 table (for example), there should > > not be any > > association entry, which associates that child to the parent, in the > > association table as well?
Thanks for the reply. I have already gone through that article, but was unable to figure out the solution. Anyways, I will give it one more try. Please note that this scenario is already there and I can't make any changes to the tables at all. Thanks - Pradeep Jindal --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
