Unlock the power of MySQL INNER JOIN! Master data retrieval with practical examples and clear explanations, seamlessly combining tables for efficient querying.
The INNER JOIN
keyword selects records that have matching values in both tables.
SELECT column_name(s)
FROM table1
INNER JOIN table2
ON table1.column_name = table2.column_name;
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 |
The following SQL statement selects all orders with customer information:
SELECT Orders.OrderID, Customers.CustomerName
FROM Orders
INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID;
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!
The following SQL statement selects all orders with customer and shipper information:
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);
#mysql #sql