Primary KEY

Question

If a primary Key consist of multiple attributes/fields then can it possible that one of the attribute/field have NULL values???

For Example ->

If a Relation R(A,B,C) have primary Key as AB then A , B both cannot be NULL but can it possible either A or B have NULL values?

Comments

both cannot be NULL but can it possible either A or B have NULL values?

no ,as here you have composite primary key than you should have each every attribute of key to be non null..!

Note: Primary key values can never be null.

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primary key can never take any NULLvalues

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Ok Thank You @shubham

Answer 1

Primary key ---> any candidate key with field value must be non null.