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#1
August 9th, 2002, 12:43 AM
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unique id
hi
what is the purpose of unique id? if you are already using a field as a primary key, why would you using unique id? does it do something special??? thanks
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#2
August 9th, 2002, 01:26 AM
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I may be wrong on this (correct me if im wrong)
But if you tell a field that its unique, if you try to add the same data twice it wont let you. Say if you had a database for products, and on that you and a field for the barcode number, you would want that to be unique, so to stop people from entering the same number, you would specify the field as unique
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#4
August 9th, 2002, 08:06 AM
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Stuie,
From what I've learned and read, you're right... You would only need to specify the field as the primary key... In Ben's example, rather than using an ID system of "1...2...3...etc", you would use the "barcode" number as the ID and have that set as the primary key... That's just my opinion!
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#5
August 9th, 2002, 08:07 AM
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