In mysql, the unique constraint is used to uniquely identify each record in a table.unique constraint on create tablethe following statement creates a unique constraint on the "id" column when the ...

With ALTER TABLE, the partial unique constraint isn't actually created correctly, right? In which case, I would prefer we disallow this since it creates a false impression of success.

I've got an interesting constraint I'm trying to add to our database. I can do with with triggers, but am curious if there is a more elegant way to do this in T-SQL (SQL2005, FWIW) We have two ...

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Embedded uniqueness constraints represent unique column combinations embedded in complete fragments of incomplete data. In contrast to SQL UNIQUE constraints, they offer a principled separation of ...

When Deleted = 1, I would like no constraint on uniqueness.<BR><BR>Is there any way to work this using SQL Server?