advanced microsoft access training courses in london - Referential Integrity

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Referential Integrity

Brian has attended:
Access Intermediate course
Access Advanced course

by - delegate Brian [4 posts] (2007 Mar 16 Fri, 16:54) Reply

Should you always enforce referential integrity when setting up relationships between tables? What would be an example if you didn't?

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RE: Referential Integrity

by - trainer Richard platinum contributer [818 posts] (2007 Mar 20 Tue, 10:15) Reply

Hi Brian.

No, you should not ALWAYS enforce referntial integrity between relationships.

Using ORDERS and CUSTOMERS tables for example:

Generally it is a good idea to enforce it one way - IE. Customer record must exist for order to be created.

You might choose not to enforce the other way - IE. If Iyou delete a customer, there is no need to delete all the orders relating to it (for record keeping), or if you delete an order, you do not want the customer to be deleted too.

Does that clarify it for you?

Richard