what is primary key and foreign key when and where have to use
Answers were Sorted based on User's Feedback
Answer / prashant
primary key has a unique & it is only one in a
databasewhile fkey is not unique. it is based on primary key
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / ramprasad.s
HI
Primary key = (Not Null + Unique).
Foreign key = (For Referential table access).
Bye
sun_ramprasad@yahoo.com
Is This Answer Correct ? | 2 Yes | 1 No |
Answer / chandrika
primary key has unique value, it dostnt contain null values
and duplicate values.
foregin key is primary key of another table
Is This Answer Correct ? | 2 Yes | 2 No |
Answer / raveendran
Primary key is unique across entire table.In primary key
not null constraint is activated.Only one primary key in
one table.
foreign key points to primary key of another table
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / csprusty
To establish a relationship between 2 tables.
pk=(unique+not null)
fk=unique
Is This Answer Correct ? | 1 Yes | 2 No |
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