Cannot modify TADODataSet after open

From: Arthur (artcheung_at_gmail.com)
Date: 10/28/04 

Date: 28 Oct 2004 11:48:57 -0700

Hi, I user Delphi 6 and open my dataset with the following code:

    sSql := 'Select Checked=
                  Case (OverrideStatus) When 0
                          then (Case State When 4 then 1 else 0 end)
                        When 1 then 1
                          When 2 then 0
                        else 0 end
             FROM ORDER';

    FADOConnection.BeginTrans;
    with ADODataSet do begin
      Close;
      ADODataSet.Connection := FADOConnection;
      CursorLocation := clUseClient;
      CursorType := ctStatic;
      LockType := ltBatchOptimistic;
      CommandType := cmdText;
      CommandText := sSql;
      Open;
    end;
    FADOConnection.CommitTrans;

then I try to modify the dataset and found that the Checked field is
readonly so I do the following:

  for iLoop := 0 to FDataSet.Fields.Count - 1 do
    ADODataSet.Fields[iLoop].ReadOnly := False;

  for iLoop := 0 to FDataSet.FieldDefs.Count - 1 do
    ADODataSet.FieldDefs[iLoop].Attributes :=
ADODataSet.FieldDefs[iLoop].Attributes - [faReadOnly];

  ADODataSet.First;
  ADODataSet.Edit;
  ADODataSet.Fields[0].AsInteger := 0;
  ADODataSet.Post;

When in debug mode, I watch the Fields[0].AsInterger and the value get
modifed after the line

  ADODataSet.Fields[0].AsInteger := 0;

however after ADODataSet.Post is ran, the value of
Fields[0].AsInterger set back to it's orignal value.

Can anyone help me with this problem... TIA