combobox下拉列表显示数据库表中的重复数据值

Question

我要在俩个COMBOBOX下拉列表中显示俩个表中的俩个字段值，可是我的程序却在下拉列表中显示重复数据值，请帮我看看程序指出错误，写出正确的代码，谢谢。
procedure Tguest_wel.FormCreate(Sender: TObject);
var
   pdata:pFieldlist;
begin
      try
      with DataModule1.ShareQuery do
      begin
              close;                       //FIELDNAME
              sql.text:='select *   from R_Standard,dept';
              open ;
              CR_Standard.Items.Clear;
              CR_Dept.Items.Clear;
      end;
  
      while not (DataModule1.ShareQuery.Eof) do
      begin
              new(pdata);
              pdata.ID:=DataModule1.ShareQuery.fieldbyname('rs_id').AsString;
              pdata.Caption:=DataModule1.ShareQuery.fieldbyname('Rs_Standard').AsString;
              CR_Standard.Items.AddObject(DataModule1.ShareQuery.fieldbyname('Rs_Standard').AsString,tobject(pdata));              pdata.ID:=DataModule1.ShareQuery.fieldbyname('Dept_Id').AsString;
              pdata.Caption:=DataModule1.ShareQuery.fieldbyname('Dept_Name').AsString;
              CR_Dept.Items.AddObject(DataModule1.ShareQuery.fieldbyname('Dept_Name').AsString,tobject(pdata));
              DataModule1.ShareQuery.Next;
      end;//while
      finally            DataModule1.ShareQuery.Close;   end;

Answer 1

select distinct xxx from ...
combobox1.items.add(query1.fieldbyname('').asstring);

Answer 2

distinct的方法我试过了，但是不管用。

Answer 3

      try
      with DataModule1.ShareQuery do
      begin
              close;                       //FIELDNAME
              sql.text:='select *   from R_Standard';
              open ;
              CR_Standard.Items.Clear;
     end;
  
      while not (DataModule1.ShareQuery.Eof) do
      begin
              new(pdata);
              pdata.ID:=DataModule1.ShareQuery.fieldbyname('rs_id').AsString;
              pdata.Caption:=DataModule1.ShareQuery.fieldbyname('Rs_Standard').AsString;
              CR_Standard.Items.AddObject(DataModule1.ShareQuery.fieldbyname('Rs_Standard').AsString,tobject(pdata));
        DataModule1.ShareQuery.Next;
      end;//while
      finally
            DataModule1.ShareQuery.Close;

Answer 4

还有这个呢！begin
      try
      with DataModule1.ShareQuery do
      begin
              close;                       //FIELDNAME
              sql.text:='select *   from dept';
              open ;
              CR_Dept.Items.Clear;
      end;
  
      while not (DataModule1.ShareQuery.Eof) do
      begin
              new(pdata);
              pdata.ID:=DataModule1.ShareQuery.fieldbyname('Dept_Id').AsString;
              pdata.Caption:=DataModule1.ShareQuery.fieldbyname('Dept_Name').AsString;
              CR_Dept.Items.AddObject(DataModule1.ShareQuery.fieldbyname('Dept_Name').AsString,tobject(pdata));
              DataModule1.ShareQuery.Next;
      end;//while
      finally            DataModule1.ShareQuery.Close;   end;

Answer 5

楼上，你的意思是这样把，但是我运行的时候程序不正确procedure Tguest_wel.FormCreate(Sender: TObject);
var
   pdata:pFieldlist;
begin
      try
      with DataModule1.ShareQuery do
      begin
              close;                       //FIELDNAME
              sql.text:='select   *   from R_Standard';
              open ;
              CR_Standard.Items.Clear;
      end;//with
      //DataModule1.ADODEPT.first;
      while not (DataModule1.ShareQuery.Eof) do
      begin
              new(pdata);
              pdata.ID:=DataModule1.ShareQuery.fieldbyname('rs_id').AsString;
              pdata.Caption:=DataModule1.ShareQuery.fieldbyname('Rs_Standard').AsString;
              CR_Standard.Items.AddObject(DataModule1.ShareQuery.fieldbyname('Rs_Standard').AsString,tobject(pdata));
      end;//while
      finally            DataModule1.ShareQuery.Close;             try
      with DataModule1.ShareQuery do
      begin
              close;                       //FIELDNAME
              sql.text:='select   *   from dept';
              open ;
              CR_dept.Items.Clear;
      end;//with
      //DataModule1.ADODEPT.first;
      while not (DataModule1.ShareQuery.Eof) do
      begin
              new(pdata);
              pdata.ID:=DataModule1.ShareQuery.fieldbyname('dept_Id').AsString;
              pdata.Caption:=DataModule1.ShareQuery.fieldbyname('dept_Name').AsString;
              CR_Standard.Items.AddObject(DataModule1.ShareQuery.fieldbyname('dept_name').AsString,tobject(pdata));
      end;//while
      finally            DataModule1.ShareQuery.Close;
   end;//try