Which constraint ensures that a column cannot accept or store an unassigned or missing value? MCQ with Answer and Explanation

Explanation:
In the relational model, a relation is a table consisting of rows and columns.

Explanation:
SAVEPOINT creates a named point within a transaction, allowing partial rollback to that point without affecting the entire transaction.

Explanation:
UPDATE is a DML statement because it is used to modify existing data values within rows of a database table, rather than modifying the structural schema.