function TSoapDataModule.ConnectDB(login:string; password:string):string;
begin
 loginVal:= login;
 passwordVal:= password;
//loginVal,passwordVal - глобальные переменные
try
ADOConnection1.Connected:= True;
result:= 'Доступ к БД разрешен';
except on e:Exception do
result:= 'Ошибка' + e.Message;
end;
end;

procedure TSoapDataModule.ADOConnection1WillConnect(
  Connection: TADOConnection; var ConnectionString, UserID,
  Password: WideString; var ConnectOptions: TConnectOption;
  var EventStatus: TEventStatus);
begin
UserID:=  loginVal;
Password:= passwordVal;
if EventStatus = esOK then Connection.LoginPrompt := False;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
Screen.Cursor:=crSQLWait;
    try
    ClientDataSet1.Active:= False;
    ClientDataSet1.Data:= ClientDataSet1.DataRequest('1');
    ClientDataSet1.Active:= True;
    finally
    Screen.Cursor:=crDefault;
    end;
end;

function TSoapDataModule.DataSetProvider1DataRequest(Sender: TObject;
  Input: OleVariant): OleVariant;
  var sqlQuery: string;
begin
with (Sender as TDataSetProvider)  do
    begin
       ADOQuery1.Active := False;
       ADOQuery1.SQL.Clear;

if Input = Null then
sqlQuery := 'SELECT * FROM cars' else
sqlQuery := 'SELECT * FROM cars WHERE id = ' + Input;
ADOQuery1.SQL.Add(sqlQuery);
ADOQuery1.Active := True;
Result:= Data;

function TSoapDataModule.ConnectDB(login:string; password:string):boolean;
begin
try
ADOConnection1.ConnectionString:= 'Provider=MSDAORA.1;Password='+ password+';User ID='+ login +'Data Source=carDB;Persist Security Info=True';
result:= 'Доступ к БД разрешен';
except on e:Exception do
result:= 'Ошибка' + e.Message;
end;
end;