Data consistency

To guarantee data consistency, the system has a recovery mechanism that trips if the PLC is shut down during a write. The recovery procedure is run at the next power-up.Considering the times needed to save data on disk, it cannot be guaranteed that samplings in the buffer memory at the time of shut-down can be transferred to the database.Nevertheless, during normal operation, all Client components that use collected data draw from the database and, simultaneously, from data in the buffer memory. From their point of view, it is as if all data were always present in the database file.