下の図は、LEFT JOIN、RIGHT JOIN、INNER JOIN、OUTER JOIN に関する 7 つの使い方を示しています。

Inner JOIN

SELECT <select_list>
FROM Table_A A
INNER JOIN Table_B B
ON A.Key = B.Key

Left JOIN

SELECT <select_list>
FROM Table_A A
LEFT JOIN Table_B B
ON A.Key = B.Key

Right JOIN

SELECT <select_list>
FROM Table_A A
RIGHT JOIN Table_B B
ON A.Key = B.Key

Outer JOIN

SELECT <select_list>
FROM Table_A A
FULL OUTER JOIN Table_B B
ON A.Key = B.Key

Left Excluding JOIN

SELECT <select_list>
FROM Table_A A
LEFT JOIN Table_B B
ON A.Key = B.Key
WHERE B.Key IS NULL

Right Excluding JOIN

SELECT <select_list>
FROM Table_A A
RIGHT JOIN Table_B B
ON A.Key = B.Key
WHERE A.Key IS NULL

Outer Excluding JOIN

SELECT <select_list>
FROM Table_A A
FULL OUTER JOIN Table_B B
ON A.Key = B.Key
WHERE A.Key IS NULL OR B.Key IS NULL

詳細については参考にしてくださいSQL 教程