常见通用的JOIN查询

SQL语句

SELECT DISTINCT
< select_list >
FROM
< left_table > < join_type >
JOIN < right_table > ON < join_condition >
WHERE 
< where_condition >
GROUP BY
< group_by_list >
HAVING
< having_condition >
ORDER BY
< order_by_condition >
LIMIT
< limit_number >

常见通用的JOIN查询

SELET < select_list >
FROM TabelA A
INNER JOIN TabelB B
on A.Key = B.Key

SELET < select_list >
FROM TabelA A
LEFT JOIN TabelB B
on A.Key = B.Key

SELET < select_list >
FROM TabelA A
RIGHT JOIN TabelB B
on A.Key = B.Key

SELET < select_list >
FROM TabelA A
LEFT JOIN TabelB B
on A.Key = B.Key
WHERE B.Key IS NULL

SELET < select_list >
FROM TabelA A
RIGHT JOIN TabelB B
on A.Key = B.Key
WHERE A.Key IS NULL

SELET < select_list >
FROM TabelA A
FULL OUTER JOIN TabelB B
on A.Key = B.Key
WHERE A.Key IS NULL

SELET < select_list >
FROM TabelA A
FULL OUTER JOIN TabelB B
on A.Key = B.Key
WHERE A.Key IS NULL OR B.Key IS NULL