what is the difference between primary key & foreign key?
Answer Posted / mathiyarasan
Primary is unique one. Each table has only one primary key.
But not allow null values.
Foreign key is opposite of primary. It is reference of
primary key from another table. It allow Null value. Each
table can have more than one foreign key.
Foreign key is used to link one to another table.
Is This Answer Correct ? | 22 Yes | 7 No |
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