TField in Memory...

[Ulfeng]

I have a requirement to add a TField in memory to an in-memory TQuery. This TQuery component is not on a data module.

The code follows: Note AField is defined as TField;
qCorrect:= TQuery.Create(nil);
with qCorrect do begin
Name := 'qCorrect';
AutoCalcFields := False;
DataBaseName := fDataBaseName;
SessionName := fCurrSessionName;
BeforeOpen := qBeforeOpen;
OnCalcFields := qCorrectCalcFields;
//persistent fields for <correct> follow....
Fields.Clear;
AField := TIntegerField.Create(qCorrect);
if Assigned(AField) then begin
with AField do begin
name := 'qCorrectnumLR';
fieldName := 'numLR';
fieldKind := fkCalculated;
ReadOnly := False;
//DisplayName := 'numLR';
required := False;
end;
Fields.Add(AField);
end;
When the OnCalcFields event fires I get an error for the calculated field that says: &quot;Error Field 'numLR' has no dataset&quot;.

Anybody know why this occurs? Thanks, Jonathan

 

[LucieLastic]

Do you not need to add some SQL to it, so it can perform the calculations on the open

 

[McMerfy]

If it says that a field has no dataset, then &quot;give&quot; it dataset

...
 if Assigned(AField) then begin
 with AField do begin
   DataSet := qCorrect; // <-- here :)
   name := 'qCorrectnumLR';
   ...
 end;

--- markus

 

[Ulfeng]

Thanks for the advice guys.