我有两张表:一.teacherblg(teacherNO,teachername,blgdepartment)
                 教师所属 (教工号,   教工名,    所属部门)
             二.teacherwkld(teacherNO,allwordload)
                 工作量     (教工号     工作量)
   在ADOTable1中我已经设置了TableName属性为“teacherblg,teacherwkld”。
    我要查找所有属于计算机系的老师的工作量,代码如下:
        ADOTable1.Close;
        ADOTable1.Filtered:=False;    ADOTable1.Filter:='(teacherblg.teacherNO=teacherwkld.teacherNO)and                                              (teacherblg.blgdepartment=''计算机系'')';
    ADOTable1.Filtered:=True;
    ADOTable1.Open;
  但是运行是发生错误,请问如何实现两表的嵌套关系查询?