Question

A self-join in a query requires the use of alias names in the FROM clause to distinguish between the two copies of the table.

Group of answer choices

True

False

Answer 1

True

Yes using self-join requires the use of alias names in the from clause to distinguish between the two copies of the table as in where tag when we have to define the equality condition of the column we have to use that different alias names of the same table to do self-join operation.

For example

SELECT a.emp_id AS "Emp_ID",a.emp_name AS "Employee Name",
b.emp_id AS "Supervisor ID",b.emp_name AS "Supervisor Name"
FROM employee a, employee b
WHERE a.emp_supv = b.emp_id;