In MySQL, is it possible to have a UNIQUE constraint on a row? -

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appears mysql's unique constraint on columns column basis, i'm looking way make sure row unique on row row basis; guessing answer create hash concatenating columns per row want unique unique on column storing hash row. also, rows unless create control unique, since id row surrogate_key; meaning it's integer sequential growing +1 of id of last row's integer.

you can create multiple-column unique index.


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