"primary key=unique+null" is equal,reson?not,reason?
Answer Posted / karunakar reddy s
primary key = unique and not null in a table
because primary key act as foreign key in other table, and
we can identify the records using this key. If pk has null
value how can we identify the records in the first table
| Is This Answer Correct ? | 8 Yes | 0 No |
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