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Composite primary keys
Message
De
02/12/2004 05:23:42
 
 
À
01/12/2004 10:57:39
Hilmar Zonneveld
Independent Consultant
Cochabamba, Bolivie
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
00966059
Message ID:
00966297
Vues:
10
>>>On the other hand, relationships between tables will be a lot simpler if you store the Primary key in a single field.
>
>>I may be biased, but I like working with composite keys. In your example, how do you established the foreign keys once you have merged two fields into one ?

>Just as with a composite key: with the REPLACE command. With a single field, you need a single REPLACE command instead of two.

I am confused now. When I am talking about establishing foreign keys, I expect to set indexes and relationships so that the VFP database will reject any attempt to enter in the child table a value which doesn't exist in the parent table. I mean, the data integrity must be enforced by the database itself and not by the code. What does this have to do with the REPLACE command ?
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