Closed Dataset after exception.
lazarus / 16-Databases

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Giu · 2011-06-25 14:10

Hi all,

I have a form (A) with a dbgrid. This form, from a button, calls
another form (B) in ShowModal. From B, i press a button, I do some
things and closes.

The problem is, thath if an exception occurs, dataset is closed.

B has this code
Code: [Select]  with dmdatos.qryInsertAsociado do
  begin
    ParamByName('artid').AsInteger :=
dmDatos.qryArticulos.FieldByName('artid').asInteger;
    ParamByName('descrid').AsInteger :=
dmDatos.qryDescriptores.FieldByName('descrid').asInteger;
    ExecSQL;
  end;
  dmDatos.SQLTransac.Commit;
  Close;
I tried this to see if dataset is not closed.
Code: [Select]  with dmdatos.qryInsertAsociado do
  begin
    ParamByName('artid').AsInteger :=
dmDatos.qryArticulos.FieldByName('artid').asInteger;
    ParamByName('descrid').AsInteger :=
dmDatos.qryDescriptores.FieldByName('descrid').asInteger;
    try
      ExecSQL;
    except
      On EDatabaseError do
      begin
        dmDatos.SQLTransac.Rollback;
        dmDatos.qryArticulos.Open;
      end;
    end;
  end;
  dmDatos.SQLTransac.Commit;
  Close;
There are some way to avoid the dataset is closed?

This application is a little application to do some tests, I don't
need to error controls for duplicate entries and so on, I only want to
dataset not be closed.

Thanks

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Lacak2 · 2011-06-27 05:39

Are you sure, that problem with "Dataset closing" is realted to some
situation when exception occurs ?
Becase, I guess, that call to "Commit" causes closing of active
datasets.
Try use instead of Commit -> CommitRetain and insteda of Rollback ->
RollbackRetain

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garlar27 · 2011-06-27 11:48

A call to .ExecSQL does not open the table. Use .ExecSQL to execute
sentences differents from "SELECT" and use .Open to open a SELECT
sentence.