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What is a CHECK constraint?

Q: What is a CHECK constraint?

A **CHECK constraint** enforces a boolean condition on column values (e.g. `CHECK (price >= 0)` or `CHECK (status IN ('a','b'))`), rejecting invalid rows at the database level so data integrity doesn't rely solely on application code.

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Explain CHECK.

check-constraint

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A CHECK constraint enforces a boolean condition on column values (e.g. CHECK (price >= 0) or CHECK (status IN ('a','b'))), rejecting invalid rows at the database level so data integrity doesn't rely solely on application code.

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SQLCHECK Constraints Playground

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