How to Use SQL INNER JOIN

SQL INNER JOIN Keyword: Main Tips

• The INNER JOIN keyword selects the pair tables rows if there is a match between in two tables columns.
• INNER JOIN acts the same as JOIN.

Syntax of SQL INNER JOIN

Selects information that has matching values in both tables.

SELECT column_name(s)
FROM mytable1
INNER JOIN mytable2 ON mytable1.column_name = mytable2.column_name;

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Demo Database

This is demo example from the "Developers" table in the database:

This is demo example from the "Orders" table in the database:

SQL INNER JOIN: Examples

The next SQL statement will return all developers with orders:

SELECT Orders.ID, Developers.Name
FROM Orders
INNER JOIN Developers ON Orders.ID = Developers.ID;

Note: the columns are matching, the INNER JOIN keyword selects the two tables rows. Customers will NOT be listed, if there is a difference between the rows.

In this example we JOIN three tables: select all orders with developer and client information:

SELECT Orders.ID, Developers.Name, Customers.Name
FROM ((Orders
INNER JOIN Developers ON Orders.ID = Developers.ID)
INNER JOIN Customers ON Orders.ID = Customers.ID);