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wahts is mean by primary key and unique key?
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Answer Posted / swapna
Primery Key:- A column or set of columns that uniquely
identify all the rows in a table. Primary keys do not allow
null values. No two rows can have the same primary key
value; therefore, a primary key value always uniquely
identifies a single row.
Unique Key:- Unique Keys are used to uniquely identify each
row in an Oracle table. There can be one and only one row
for each unique key value. no value repeate in the other
rows of the same table.
| Is This Answer Correct ? | 21 Yes | 7 No |
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