SQL INNER JOIN Keyword

SQL INNER JOIN Keyword : SQL INNER JOIN keyword selects records that have matching values in both tables.

INNER JOIN Syntax

SELECT column_name(s)
FROM table1
INNER JOIN table2 ON table1.column_name = table2.column_name;

Demo Database

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

Below is a selection from the “Orders” table:

OrderID CustomerID EmployeeID OrderDate ShipperID
10308 2 7 1996-09-18 3
10309 37 3 1996-09-19 1
10310 77 8 1996-09-20 2

And a selection from the “Customers” table:

CustomerID CustomerName ContactName Address City PostalCode Country
1 Alfreds Futterkiste Maria Anders Obere Str. 57 Berlin 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 05021 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 05023 Mexico

SQL INNER JOIN Example

The following SQL statement selects all orders with customer information:

Example

SELECT Orders.OrderID, Customers.CustomerName
FROM Orders
INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID;

 

Output

Number of Records: 11

OrderID CustomerName
10248 Wilman Kala
10249 Tradição Hipermercados
10250 Hanari Carnes
10251 Victuailles en stock
10252 Suprêmes délices
10253 Hanari Carnes
10254 Chop-suey Chinese
10255 Richter Supermarkt
10256 Wellington Importadora
10257 HILARIÓN-Abastos
10258 Ernst Handel

 

Note:

The INNER JOIN keyword selects all rows from both tables as long as there is a match between the columns. If there are records in the “Orders” table that do not have matches in “Customers”, these orders will not be shown!

 JOIN Three Tables

The following SQL statement selects all orders with customer and shipper information:

Example

SELECT Orders.OrderID, Customers.CustomerName, Shippers.ShipperName
FROM ((Orders
INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID)
INNER JOIN Shippers ON Orders.ShipperID = Shippers.ShipperID);

 

Output

Number of Records: 8

OrderID CustomerName ShipperName
10248 Wilman Kala Federal Shipping
10249 Tradição Hipermercados Speedy Express
10250 Hanari Carnes United Package
10251 Victuailles en stock Speedy Express
10252 Suprêmes délices United Package
10253 Hanari Carnes United Package
10254 Chop-suey Chinese United Package
10255 Richter Supermarkt Federal Shipping

 

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