what are the advantages of primary key over unique+notnull
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Answer Posted / kamal
we are able to create a primary key for combination of more
than 1 column. which is not possible in Unique,we should
create unique key for each and every column in the table
individually.
ex . we can create a primary key for (Name,DOB,address)- ie
combination of these three columns be unique.
| Is This Answer Correct ? | 3 Yes | 5 No |
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