I solved the problem with another solution.
type
TInternalQuery = class(TQuery)
protected
procedure InternalInitFieldDefs; override;
public
constructor Create(AOwner: TComponent; const qryGen: TQuery); reintroduce;
end;
constructor TInternalQuery.Create(AOwner: TComponent; const qryGen: TQuery);
var
intCont: Integer;
begin
inherited Create(AOwner);
Self.DatabaseName := qryGen.DatabaseName;
Self.UpdateObject := qryGen.UpdateObject;
Self.SQL.Text := qryGen.SQL.Text;
for intCont := 0 to Self.ParamCount - 1 do
begin
Self.Params[intCont].Value := qryGen.Params[intCont].Value;
end;
end;
procedure TInternalQuery.InternalInitFieldDefs;
var
intCont: Integer;
begin
inherited InternalInitFieldDefs;
for intCont := 0 to FieldDefs.Count - 1 do
begin
if (FieldDefs[intCont].Size = 0) and (FieldDefs[intCont].DataType = ftBCD) then
begin
FieldDefs[intCont].Precision := 64;
FieldDefs[intCont].Size := 32;
end;
end;
end;
the problem is ((FieldDefs[intCont].Size = 0) and (FieldDefs[intCont].DataType = ftBCD)). when ClientDataSet is created, the field is truncated, because when oracle has a function like "SUM(TOTAL)" the result field is created with size 0, so the clientdataset handle the field as Integer field.