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OldTransactionBehaviour := True; //The new transactions system does really not work for me (way to much work)..

displaydataset := TUniQuery.Create(nil);
displaydataset.Connection := MyConnection;
displaydataset.Sql.text := 'select * from whatever');
displaydataset.Open;

connection.StartTransaction;
lookupQuery := TUniQuery.Create(nil);
lookupQuery.Connection := MyConnection;
lookupQuery.Sql.text := 'select * from whatever');
lookupQuery.Open;
..something
connection.CommitTransaction; // <-- This closes the displaydataset and lookupquery as well (didn't expect that)..

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procedure TDATransaction.CloseDataSets;
var
  i,j: Integer;
begin
  for i := 0 to FConnections.Count - 1 do begin
    if not FConnections[i].IsMultipleTransactionsSupported then
      continue;

    for j := 0 to FConnections[i].DataSetCount - 1 do
      if FConnections[i].DataSets[j] is TCustomDADataSet then begin
        //if TCustomDADataSet(FConnections[i].DataSets[j]).UsedTransaction = Self then
          //TCustomDADataSet(FConnections[i].DataSets[j]).ConnectChange(FConnections[i], False);//We can't use SendConectEvent(False)
      end
      else
      if FConnections[i].DataSets[j] is TDAMetaData then begin
        if TDAMetaData(FConnections[i].DataSets[j]).UsedTransaction = Self then
          TDAMetaData(FConnections[i].DataSets[j]).ConnectChange(FConnections[i], False);//We can't use SendConectEvent(False)
      end;
    for j := 0 to TCustomDAConnection(FConnections[i]).FSQLs.Count - 1 do
      if TCustomDASQL(FConnections[i].FSQLs[j]).UsedTransaction = Self then
         TCustomDASQL(TCustomDAConnection(FConnections[i]).FSQLs[j]).ConnectChange(FConnections[i], False);
  end;
end;

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while not qryCustomer.Eof
  Connection.StartTransaction;
  donate 1 dollar (insert into etc etc)
  Connection.CommitTransaction; //Closes qryCustomer (thats cheap!)?
  qryCustomer.Next;
end;

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//MMWIN:CLASSCOPY
unit _MM_Copy_Buffer_;

interface

type
  {* TUniConnectionHelper: Wrapper maybe better than changing source code *}
  TUniConnectionHelper = class helper for TUniConnection
{$REGION 'Notes'}
    {Reintroduces these methods to allow us to easily implement Transactions that work with all Providers:

      Dataset.AutoCommit := False;     // Turn off InterBase AutoCommit, does nothing for SQLServer
      with UniScript.Connection do
      begin
      ....StartTransaction;
      ....try
      .......do Stuff..
      ....except
      ......Rollback;
      ......Raise;
      ....end;
      ..Commit;
      end}
{$ENDREGION}
  private
  public
    procedure Commit;
    procedure Rollback;
    procedure StartTransaction;
 end;


implementation


{* TUniConnectionHelper *}

procedure TUniConnectionHelper.Commit;
begin
  if not InTransaction then Exit;

  if (ProviderName = GetProviderName(dbFirebird)) then CommitRetaining
  else if (ProviderName = GetProviderName(dbSQLServer)) then inherited
  else raise Exception.CreateFmt('Provider: "%s" not implemented', [ProviderName]);
end;

procedure TUniConnectionHelper.Rollback;
begin
  if not InTransaction then Exit;

  if (ProviderName = GetProviderName(dbFirebird)) then RollbackRetaining
  else if (ProviderName = GetProviderName(dbSQLServer)) then inherited
  else raise Exception.CreateFmt('Provider: "%s" not implemented', [ProviderName]);
end;

procedure TUniConnectionHelper.StartTransaction;
begin
  if not InTransaction then inherited;
end;

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  Tr1 := TUniTransaction.Create(nil);
  Tr1.DefaultConnection := MyConnection;
  displaydataset := TUniQuery.Create(nil);
  displaydataset.Connection := MyConnection;
  displaydataset.Transaction := Tr1;
  displaydataset.Sql.Text := 'select * from whatever';
  displaydataset.Open;

  MyConnection.StartTransaction;
  lookupQuery := TUniQuery.Create(nil);
  lookupQuery.Connection := MyConnection;
  lookupQuery.Sql.Text := 'select * from whatever';
  lookupQuery.Open;
  MyConnection.Commit;