Difference between Primary key and unique key?
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Answer / deepali b. baviskar
Unique key can be NULL but Primary key couldn't be NULL.
| Is This Answer Correct ? | 11 Yes | 0 No |
Answer / sraboni mondal
primary key is a key which is totally unique key and unique
has null values
| Is This Answer Correct ? | 0 Yes | 1 No |
Answer / sohini ghosh
In RDBMS, a unique key can uniquely identify each row in a
table, and is closely related to the Super key concept. A
unique key comprises a single column or a set of columns.it
can be null.
A primary key is a special case of unique key. Primary keys
may consist of a single attribute or multiple attributes in
combination.It can't be null..
| Is This Answer Correct ? | 0 Yes | 2 No |
Answer / keerthi
primary key is a field that can serve as unique identifier in table.ex:customer id.
| Is This Answer Correct ? | 1 Yes | 4 No |
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