What is a Self-Join?

1.	What is a Self-Join?
Answer» A self JOIN is a case of REGULAR join where a table is joined to itself BASED on some RELATION between its own column(s). Self-join uses the INNER JOIN or LEFT JOIN clause and a table alias is used to assign different names to the table within the query. SELECT A.emp_id AS "Emp_ID",A.emp_name AS "Employee",B.emp_id AS "Sup_ID",B.emp_name AS "Supervisor"FROM employee A, employee BWHERE A.emp_sup = B.emp_id;

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