不明白,你到底要得到什么样的查询结果 ,是以 A表主(left join ) ,还是以B表为主 (right join),还是显示两表中的所有记录(两表记录数之积) (楼上的SQL即可) SELECT A.name,B.name FROM A a left join B b on a.ID=a.pid WHERE b.name="xx" group by a.name ; SELECT A.name,B.name FROM A a right join B b on a.ID=a.pid WHERE b.name="xx" group by a.name ;
select A.ID, A.名称 from A join B on A.ID=B.PID where B.名称='王1'
SELECT A.name,B.name FROM A a left join B b on a.ID=a.pid WHERE b.name="xx" group by a.name ;
SELECT A.name,B.name FROM A a right join B b on a.ID=a.pid WHERE b.name="xx" group by a.name ;