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What is SELF JOIN and when would you use it?

What  is SELF JOIN and when would you use it?

A SELF JOIN is join which is used to join a table to itself.

There is no SELF JOIN keyword and it is used to compare values in a column with other values in the same column in the same table.

For Example,

SELECT * FROM TableA t1, TableA t2
WHERE t1.Id = t2.Id

In the above query, WHERE clause could be any given expression as per you!


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