Thx Eric, Clear, this is what I suspected and was hoping for. It concerns an Oracle DB app I'm working on.
If I was to relate this to Criteria could I achieve what you explain by joining the necessary tables together, there may be three or four that I would have to update. Instead of actually deleting the records we set them to inActive. /c > Colin > > > Scouring the schema the other day I came across the two settings below concerning foreign-keys. I'm currently not using them. Can anyone (briefly) explain their use, and is anyone actually using them? > > If these correspond to their RDBMS equivalents, and I'm guessing they do > although I don't currently use them, then they both deal with preserving > referential integrity. > > > on delete set null > > will set foreign keys to null when you delete a related row. > > For a simple example, you have a Customer table and an Order table. > > Customer | Order > -------- | --------- > customerId | orderId > customerName | customerId > > A one-to-many relationship exists between Customer and Order via the > customerId key, so that a Customer can have many Order entries. If you > delete a Customer and "on delete set null" is active, then the Order > table will receive a > > UPDATE Order SET customerId = null WHERE customerId = [the one you > deleted] > > This will disolve the relationship and preserve referentail integrity. > > > on update cascade > > will update all related foreign keys. So, if you change customerId on a > Customer row, the Order table will receive a > > UPDATE Order SET customerId = [new customerId] WHERE customerId = [old > customerId] > > Does that help? > > Eric > > -- > Eric Emminger > [EMAIL PROTECTED] > > > -- > To unsubscribe, e-mail: <mailto:turbine-torque-user-unsubscribe@;jakarta.apache.org> > For additional commands, e-mail: <mailto:turbine-torque-user-help@;jakarta.apache.org> > > -- To unsubscribe, e-mail: <mailto:turbine-torque-user-unsubscribe@;jakarta.apache.org> For additional commands, e-mail: <mailto:turbine-torque-user-help@;jakarta.apache.org>
