What?s the difference between PRIMARY KEY and UNIQUE in
MyISAM?
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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