SQL INNER JOIN Keyword
The 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;
FROM table1
INNER JOIN table2 ON table1.column_name = table2.column_name;
SQL INNER JOIN Example
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;
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!
JOIN Three Tables
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);
FROM ((Orders
INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID)
INNER JOIN Shippers ON Orders.ShipperID = Shippers.ShipperID);
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