Always use a surrogate primary key - one that has no meaning attached to it. Use the auto inc or SYS(2015) to generate one.
>I have a table called Product with a field called ProductID, and the ProductID is the primary key of the table.
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>When a user creates a record with ProductID = 'ABC', and then deletes it, and then creates it again, i receive a dup primary key error, because the deleted record still exists as a marked-delete record.
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>I would like to know how can i create a primary key on ProductID without this problem?
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>Thanks,
>David Fung