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Base de données, Tables, Vues, Index et syntaxe SQL
>>>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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