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  1. Which clause in the SQL standard controls how NULL values in a composite foreign key are handled when comparing to a primary key.
    1. ON CASCADE
    2. ON DELETE
    3. SET
    4. MATCH
    5. None of these
Correct Option: D

The MATCH clause in the SQL standard controls how NULL values in a composite (multiple-column) foreign key are handled when comparing to a primary key. MySQL essentially implements the semantics defined by MATCH SIMPLE.



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