# SQL Self JOIN

### SQL Self JOIN

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

#### Self JOIN Syntax

```sql
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:<br>

![](https://826093633-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LS8lPNzCGPR5-DLbGXv%2F-LSY-waNYjqnNNKdvlkO%2F-LSY0N6cnx0JjfnNVpZC%2Fimage.png?alt=media\&token=d5041b95-bad6-48e4-b8b7-cac0c67c6562)

\
SQL Self JOIN Example

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

```sql
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;

```


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