[Opensource] referencial integrity

[CR]

Hi Stephen

I try to explain what it means.
Referencial integrity means how the database checks the there are only valid rows in child table wich has an relationship with a master table.

You have a master tabel MASTER with it primary key ID. The secand table, the child, is called CHILD. Now Child has a special Primary key. Its own CHILD_ID and the MASTER tables ID (called MASTER_ID).

Now referencial integrity checks every value for MSTER_ID in CHILD has an equal in the field ID in the MASTER table. Therefore you can not insert unvaild values for MASTER_ID in CHILD table.

Hope that helps a bit.

Regards

Chris
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