what is the difference between unique and primary key
Answer Posted / suresh kumar somayajula
Unique Key allows NULL value and a table can have more than
one UNIQUE KEY Constraint.
Primary Key is the combination of UNIQUE+NOT NULL,means it
won't allow NULL Values and a table can have only one
Primary Key.But a table can have Composite Primary Key.
Thank you,
Suresh
| Is This Answer Correct ? | 4 Yes | 0 No |
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