what is the difference between primary key & foreign key?
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Answer Posted / ansul singh
Primary key is unique key but Foreign key always refers to
primary key.
Primary key is the parent & Foreign key is the child.
Primary key is unique, Primary key is not null and
Foreign key is null, Foreign key reference as primary key
is another table.
Primary key will not allow "Null values" & "Duplication
values",
Foreign key will allow "Null values & "Duplicate values" &
it refers to a primary key is another table.
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