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Foreign key constraints?

JS
I have two tables, T1 and T2.

T1 has a foreign Key that refers to a key in T2.

The way that I see it, its only possible to insert something into T1 if
there already exists a tuple in T2 with the same value in key.

That means that I always have to insert something into T2 before inserting
into T1

Is that correct?
Jul 23 '05 #1
1 1186
Yes. This is how you enforce business rules like "Don't take orders
for things we do not have in inventory."

Jul 23 '05 #2

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