what is Primary key and unique key and what is the
Difference?

Answer Posted / arun prasad

PRIMARY KEY IS A FIELD WHICH IS USED TO IDENTIFY THE TABLE
AND THESE CANNOT BE CHANGED, IF IT IS CHANGED THE DATA
INTEGRITY WILL GET LOST.

UNIQUE KEY IS A GROUP OR A SINGLE FIELD WHICH IS USED TO
REPRESENT THE NUMERIC FIELDS WHICH DOESNT CHANGE.
THE GROUP OF NUMERIC FIELDS IS THE UNIQUE KEY.

PRIMARY KEY IS USED FOR DATABASE TABLES WHERE AS UNIQUE KEY
IS USED FOR INTERNAL TABLES.

Is This Answer Correct ?    4 Yes 13 No



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