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what is candidate key & primary key,different b/t the two?
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Answer Posted / uday shankar dokku
candidate key: when we reduce unnecessary columns from a
super key it is called as candidate key
primary key: primary key is a constraint, in a table
there is only one primary key,a primary key is simple or
composite, a simple primary key is based on one column which
can be specified either inline outline of the constraint,a
composite primary key is based on (2-32)columns which can
be specified only out line of the constraint,a primary dose
not allows duplicates.
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