emp numb is unique because that is primary key,,but what is foreign key .. explain very clear with example
Answer / vilas
Foregin key: It is the relation between two tables.it can be
used to create the relation between two tables,when two
tables have the unique rows (means emp_numb)then we can
used to foreign key.
eg:
create table student
{ name varchar(10),
rollno int(10));
.......this is student table........
create table student_Details
{ name varchar(10),
rollno int(10)refercence
);
.
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