-- 查找两个表中ID相等的 select a.id, a.name,b.math from stu a,scores b where a.id = b.id -- 右外连接 select b.id, a.name,b.math from stu a,scores b where a.id(+) = b.id select b.id, a.name,b.math from stu a right outer join scores b on a.id = b.id -- 左外连接 select…