有关子查询的问题

Question

if radiobutton7.Checked then
  //try
  begin
    with rqADOQuery do
    begin
      sql.Clear;
      sql.Add('select 栋号 from dh where 栋号= :栋号');
      parameters.ParamByName('栋号').Value := Edit5.Text;
      open;
      if Recordcount <> 0 then
      begin
        with rqADOQuery do
          begin
            sql.Clear;
            sql.Add('select 房号 from (select 栋号 from dh where 栋号= :栋号) where 房号= :房号');
            parameters.ParamByName('房号').Value:=Edit6.Text;
            parameters.ParamByName('栋号').Value:=Edit5.Text;
            open;
            if recordcount <> 0 then
              begin
                Messagedlg('房号<'+Edit6.Text+'>已有住户',mterror,[mbok],0);
                Exit;
              end
            else
              with rqADOQuery do
              begin
              sql.Clear;
              sql.Add('insert into (select 栋号 from dh where 栋号= :栋号1)(序号,栋号,房号,姓名,类型,面积,单价,缴费状态) values(:序号,:栋号,:房号,:姓名,:类型,:面积,:单价,:缴费状态)');
              parameters.ParamByName('栋号1').Value:=Edit5.Text;
              parameters.ParamByName('序号').Value:=listview2.Items.Count+1;
              parameters.ParamByName('栋号').Value:=Edit5.Text;
              parameters.ParamByName('房号').Value:=Edit6.Text;
              parameters.ParamByName('姓名').Value:=Edit7.Text;
              parameters.ParamByName('类型').Value:=Edit8.Text;
              parameters.ParamByName('面积').Value:=Edit9.Text;
              parameters.ParamByName('单价').Value:=Edit10.Text;
              parameters.ParamByName('缴费状态').Value:=Edit11.Text;
              sql.Add('update (select 栋号 from dh where 栋号= :栋号2) set 月应收费用=面积*单价,日收滞纳金比例= :日收滞纳金比例');
              parameters.ParamByName('日收滞纳金比例').Value:=Edit1.Text;
              parameters.ParamByName('栋号2').Value:=Edit5.Text;
              execsql;
              end;
          end;
      end
      else
        begin
        try
        with rqADOQuery do
        begin
        sql.Clear;
        sql.Add('insert into dh(栋号,标识) values(:栋号,:标识)');
        parameters.ParamByName('栋号').Value:=Edit5.Text;
        parameters.ParamByName('标识').Value:='1';
        execsql;
        end;
        except
          messagedlg('程序异常！',mterror,[mbok],0);
          exit;
        end;        //try
        with ADODataSet1 do
        begin
          close;
          commandtext:='creattb';
          open;
          parameters.Clear;
        end;
        //except
          //messagedlg('程序异常！',mterror,[mbok],0);
        //end;
        end;
      close;
    end;
  end;请教各位   我运行时他提示我where附近有语法错误  我没搞明白怎么回事

Answer 1

sql.Add('insert into (select 栋号 from dh where 栋号= :栋号1)(序号,栋号,房号,姓名,类型,面积,单价,缴费状态) values(:序号,:栋号,:房号,:姓名,:类型,:面积,:单价,:缴费状态)');select 栋号 from dh where 栋号= :栋号1   查出来的只有"栋号"这一个字段