A method for updating a data base which includes positioning data and identity information of a cell, the method comprising receiving a position of a device and receiving identity information of a cell. The data base is examined to find parameter information relating to the received identity information. The parameter information is retrieved from the data base. It is determined whether the data base is to be updated with the position data of the device, wherein if it is determined that the data base is to be updated, the updating of the data base is performed by using the position data of the device and the value of an updating parameter is updated.