关键字只要其中某个表存在匹配,FULL JOIN 关键字就会返回行。 FULL JOIN 关键字语法 SELECT column_name(s) FROM table_name1 FULL JOIN table_name2 ON table_name1.column_name=table_name2.column_name 注释:在某些数据库中, FULL JOIN 称为 FULL OUTER JOIN。 原始的表"Persons" 表: Id_P LastName FirstName Address City 1 Adams John Oxford Street London 2 Bush George Fifth Avenue New York 3 Carter Thomas Changan Street Beijing