SQL SELF JOIN

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The SELF JOIN is used to join the table to itself that why it is known as SELF JOIN.

Syntax: 

SELECT columnList FROM table1 t1, table1 t2 WHERE t1.commonColumn = t2. commonColumn;

Example:

SELECT emp1.EMP_NAME FROM EMPLOYEE emp1, EMPLOYEE emp2 
WHERE emp1.AGE = emp2.AGE;

Output:

EMP_NAME
Parmender
Nidhi
Parmender
Parbhjot
Parmender
Nidhi
Parmender
Parbhjot
Parmender
Nidhi

 
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