Java中的SQL语句问题，求解决

Question

有chengji表（Id,Tno,Sno,jiaoxuefenwei,jiaoxuenengli,jiaoxueneirong,zongh)
Teacher表（Tno，Tname）
SQL语句
select Tno,Tname,jiaoxuefenwei,jiaoxuenengli,jiaoxueneirong,zonghe from chengji join Teacher on chengji.Tno=Teacher.Tno where Tname='"+str+"'"
正确吗？
怎么修改

Answer 1

"select b.Tno,b.Tname,a.jiaoxuefenwei,a.jiaoxuenengli,a.jiaoxueneirong,a.zonghe from chengji a join Teacher b on a.Tno=b.Tno where b.Tname='"+str+"'"