MySQL各种Join

[左连接]    SELECT FROM TableA A LEFT JOIN TableB B ON A.Key = B.Key 

[右连接]    SELECT FROM TableA A RIGHT JOIN TableB B ON A.Key = B.Key

[左外连接] SELECT FROM TableA A LEFT JOIN TableB B ON A.Key = B.Key WHERE B.Key IS NULL

[右外连接] SELECT FROM TableA A LEFT JOIN TableB B ON A.Key = B.Key WHERE A.Key IS NULL

[内连接]    SELECT FROM TableA A INNER JOIN TableB B ON A.Key = B.Key

[满连接]    SELECT FROM TableA A FULL OUTER JOIN TableB B ON A.Key = B.Key

[左连接]    SELECT FROM TableA A FULL OUTER JOIN TableB B ON A.Key = B.Key WHERE A.Key IS NULL OR B.Key IS NULL