Walter Meester
HoogkarspelPays-Bas
>Rule 8: All tables have primary keys.
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>I agree when one is doing new development or can add the keys to an old system during conversion.
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>HOWEVER, when you have a Clipper system that has been in use for 17 years and converting the entire system will take 2-3 years, some proper design techniques have to wait. The problem is that some of the Clipper code has to run in parallel with the VFP code and without changing code in 2 systems, primary can only be used sparingly.
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>I'm posting this as an exception. After 15 years of working on lots of systems written by someone else, I've learned that "Never is a very long time!!!"
So true. I've been maintaining systems with tables without primary keys which work fine. In some cases having no primary key isn't that much of a problem.
For all new systems I develop I always use a PK, for convinient reason.
Walter,
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