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Is primary key = unique key,not null?
If yes,please explain
IF No,please explain
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Answer Posted / chanchal
a primary key can be a unique key but a unique key
may be or may not be a primary key bcoz primary key cant be
NULL but Unique Key may.
in a table more than one unique key but only one primary key
| Is This Answer Correct ? | 5 Yes | 0 No |
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