what are the advantages of primary key over unique+notnull
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Answer Posted / shilpa.oracle
Primary key accepts only unique values and does not allow
null values.
Unique key accepts unique values and allows null values.
not null constraint allows duplicate values and doesnt allow
null values.
When a primary key constraint or unique key constraint is
created by default index is created on the columns with
these constraints.
| Is This Answer Correct ? | 16 Yes | 4 No |
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