Primary Key 1. Not Null 2. One primary key can be defined at on table

Difference between primary key and unique key ?

Question Posted / satendra dixit

Answer Posted / satendra dixit

Primary Key
1. Not Null
2. One primary key can be defined at on table

Unique Key
1. May be Null
2. one or more then 1, can be implemented

Is This Answer Correct ?

22 Yes

11 No

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