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Base de données, Tables, Vues, Index et syntaxe SQL
>>I may add to Hilmars that if you add the pk to the view, a concurent view somewhere else will not know about the new pk and may use it also. You will not know when a new view - record is written to its table. Then you will have two new records (in view) with the same pk.
>
>You can overcome this problem by using GUIDs for your primary keys. And there are some instances where you may need the primary key before you save the view to it's table. For example, if you add a child record in a child view, you will want to populate it's foreign key with the parent's primary key.
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>Regards,
>
>Jim
In this scenario you have to create the PK in the view. I use views mostly for children tables, so I did not thought about this.
I store the PK in a separate table, so I don't need GUIDs. If I create twice the PK (in the table and in the view), I thought I was wasting PKs; to my surprise it was not the case. I have to research deeper to know why didn't VFP created twice the PK.
Besides, I was not really concerned about wasting PK, as with an integer type I get 4 billion PK (including negative integers).
Thanks,
Javier.
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