Marius0188
asked on
Delphi 7 :: TADOQuery OnAfterScroll Error with parameters
Dear Experts,
I have 2 TDBGrid components.
The 1st one must display master table records and the second one displays detail table records
for the selected row in the master table.
qOrders = Master Query
qParts = Detail Query.
On qOrders' OnAfterScroll event I have the following code:
**** PS: See code snippet.
When my application starts up I receives and error:
"EDatabaseError with message 'qParts: Parameter 'POrderNumber' not found'...."
This parameter does exist and when I click the error message away the application starts up and
when scrolling through the master dbgrid the code is working 100%. It is only when the app starts up when I receive this error. After that, it is working as expected.
What can possible be wrong?
Please help.
I have 2 TDBGrid components.
The 1st one must display master table records and the second one displays detail table records
for the selected row in the master table.
qOrders = Master Query
qParts = Detail Query.
On qOrders' OnAfterScroll event I have the following code:
**** PS: See code snippet.
When my application starts up I receives and error:
"EDatabaseError with message 'qParts: Parameter 'POrderNumber' not found'...."
This parameter does exist and when I click the error message away the application starts up and
when scrolling through the master dbgrid the code is working 100%. It is only when the app starts up when I receive this error. After that, it is working as expected.
What can possible be wrong?
Please help.
procedure TPickingListFrame.qOrdersAfterScroll(DataSet: TDataSet);
begin
inherited;
If qOrders.IsEmpty then Exit;
qParts.Close;
qParts.SQL.Clear;
qParts.SQL.Text := 'SELECT POrderNumber, ItemNumber, ItemDescription, Qty FROM tblCallOff WHERE '+
'(POrderNumber = :POrderNumber) AND (Deleted = :Deleted) ORDER BY ItemNumber';
qParts.Parameters.ParamByName('POrderNumber').Value := qOrders.FieldByName('POrderNumber').AsString;
qParts.Parameters.ParamByName('Deleted').Value := 0;
qParts.Open;
end;
in case that the sql don't change during runtime (except the parameterValues),
you could simple close, set the parameter and open again
(a clear and new set of the sql is not needed then)
(would be also raise the performance)
meikl ;-)
you could simple close, set the parameter and open again
(a clear and new set of the sql is not needed then)
(would be also raise the performance)
meikl ;-)
Is your DBConnection and your qOrders/qPart opened at designtime? Close them before you launch you application.
are you sure the error from "qOrdersAfterScroll" event
Change component creation order of these two components.
(qOrders,qParts)
(qOrders,qParts)
Set Active property of qOrders equal to false. then open this dataset in the "formcreate" event.
procedure TPickingListFrame.FormCrea
begin
qOrders.Open;
end;
procedure TPickingListFrame.FormCrea
begin
qOrders.Open;
end;
Don't open on TPickingListFrame.FormCrea
This will by-pass creation order issues as well.
This will by-pass creation order issues as well.
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as the questioner itself didn't response to any comment which wass done, so that any advice due lack of feedback could be/ could not be right, i would recommend to delete this question
meikl ;-)
meikl ;-)
Forced accept.
Computer101
EE Admin
Computer101
EE Admin
meikl ;-)