Oracle 表A上有个字段aa,aa有4种值(1,2,3,4),字段aa如果等于1就查询B1...答:select t.* from(select a.aa,xx,yy,zz,'b1' table_name from a,b1 where a.aa=b1.id and b1.n=23union allselect a.aa,xx,yy,zz,'b2' table_name from a,b2 where a.aa=b2.id and b2.n=18union allselect a.aa,xx,yy,zz,'b3' table_name from a,b3 where...