SQL Self JOIN or NATURAL JOIN With Example

SQL Self JOIN

A self JOIN occurs when a table takes a 'selfie'.
A self JOIN is a regular join but the table is joined with itself.
This can be useful when modeling hierarchies.
They are also useful for comparisons within a table.

The SQL Self JOIN syntax

The general syntax is:

SELECT column-names FROM table-name T1 JOIN table-name T2 WHERE condition

T1 and T2 are different table aliases for the same table

SQL Self JOIN Examples

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