When running projects in Merbon SCADA, when the service is switched on, a file with the .datax extension is created after loading the projects. This file is created only when the project is successfully loaded in SCADA. Therefore, if there is a fatal error in the project that prevents the project from running, the .datax file is not created.
The .datax file is an image of the .data file where the data point definitions are located. When exporting a project from RcWare, in addition to the data point properties, the default value of the data point corresponding to the value at the time of export from RcWare is written to the .data file. The .data file is therefore rather immutable and is only used to create a table of data points. The .datax file is used to dynamically save changes in values and settings at runtime. Whenever SCADA detects a change in settings or values from a .data file, this information is written to the .datax file. The interval in which changes are recorded is fixed at 30 seconds. In each interval, the .datax file is then merged with other .data files. This file has the highest priority. When the merging process begins, all data points are read from the .data file first. It is then determined whether the .datax file contains any information about these points. If so, this information is displayed in Merbon SCADA, if not, the information from the original .data file is used.
The .datax file grows gradually as the project runs, up to the size of the .data file. A file of the .diff.datax type is also introduced to prevent the reading of current values from being slowed down. This file only contains changes made in the last few merge intervals and will start saving if the .datax file grows to a certain size. These changes are left here until (in the order of minutes = 5...6x30s interval), when they are written to the .datax file and replaced by new changes. The advantage of this method is that the changes are read from a file with a size of several kb, so the whole process is faster and the disk of the physical server is not so much used.
