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Proper Way To Check For Duplicate Primary Key
Message
De
26/06/2001 11:04:47
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
00522709
Message ID:
00523585
Vues:
16
>>What is the most efficient way of handling this?
>>Assuming I have a compound PKEY or CANDIDATE
>>should I do a SEEK before modifying a one of
>>the components or is it more efficient to trap
>>for the error?
>>
>>   ...kt
>
>Really IMHO the proper way to do this is to generate the primary key yourself, and make sure its unique when generated. This means either use a table to keep track of keys generated for each table, or come up with a key routine that will always give you a unique value, something along the lines of SYS(0)+SYS(2015) which should pretty much guarantee a unique value.

That's a lot of people's HO :-)

Ok, well let's remove Pkeys from the discusssion. That's
not really what I'm getting at. Let me amened the question
to whether it is more efficient to check for a duplicate
value in a CANDIDATE key by trapping for an error
or doing a seek on any CANDIDATE key(s) before doing an
add or change.
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