An integral part of the data flow system are data bases. The access to modify a data base itself will be limited to the manager(s) of the data base. The manager(s) should provide a proper interface to access the data base and define the format of information for the data base. As all the different subsystems (TCS, instruments, detector, etc.) will interact with the data bases an overview will be made of the kind of information that is required for the data base in relation with things like calibration plans, reduction pipelines, etc., from the different subsystems and the way and/or format in which this should be provided.