What?s the difference between PRIMARY KEY and UNIQUE in
Answers were Sorted based on User's Feedback
Answer / amith
PRIMARY KEY cannot be null, so essentially PRIMARY KEY is
equivalent to UNIQUE NOT NULL
|Is This Answer Correct ?||28 Yes||8 No|
Answer / niraj kumar
primary key is not accept the null value.primary key is
always autoincrement.unique key is accept the one null
value.it is not a autoincrement.
|Is This Answer Correct ?||4 Yes||15 No|
Answer / manish
Primary Keys are used in building relationships between
tables in a database. (an index is automatically created on
the primary key). The difference between primary and
ordinary keys is that there can be multiple keys, but only
one primary key.
|Is This Answer Correct ?||7 Yes||20 No|
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