Difference between primary key and unique key ?
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Answer Posted / umapathy.r
The column holding the primary key constraint cannot accept
null values.whereas colum holding the unique constraint can
accept null values assume that t3 is a table with two
columns t1 having primary key constraint and t2 having
unique constraint if u try to insert null into t2 it will
accept that values whereas column t1 will not accept null
| Is This Answer Correct ? | 1164 Yes | 121 No |
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