From OpenSCADAWiki
Connection is made by creating a new database object in the module of the required type of the subsystem "DB" and its subsequent configuration (read more). After the DB creation, configuration and enabling you can immediately download the DB data from it by clicking the "Load the program from this DB" on the form of the database object. However, this only involves loading, without enabling-starting the downloaded objects, so that may be easier to restart OpenSCADA.