SQL語句各類join用法（圖文）

一、INNER JOIN(內鏈接) select * from table A A inner join table B B on A.key = B.key //內鏈接 二、LEFT JOIN(左鏈接) select * from table A A left join table B B on A.key = B.key //左鏈接 三、RIGHT JOIN(右鏈接) select * fro

>>阅读原文<<