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      • SQL INNER JOIN Keyword
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  • SQL Self JOIN
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  1. Data Query Language
  2. SQL Joins

SQL Self JOIN

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Last updated 6 years ago

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SQL Self JOIN

A self JOIN is a regular join, but the table is joined with itself.

Self JOIN Syntax

SELECT column_name(s)
FROM table1 T1, table1 T2
WHERE condition;

Demo Database

In this tutorial we will use the well-known Northwind sample database.

Below is a selection from the "Customers" table:

SQL Self JOIN Example

The following SQL statement matches customers that are from the same city: 

SELECT A.CustomerName AS CustomerName1, B.CustomerName AS CustomerName2, A.City
FROM Customers A, Customers B
WHERE A.CustomerID <> B.CustomerID
AND A.City = B.City 
ORDER BY A.City;