A hierarchy of object groups is defined. Objects group collections are defined on top of the hierarchy. Authorization rights for executing actions are defined through the object group collection definitions. A request for a change associated with assignments of an object group in a hierarchy of a plurality of object groups may be received, where the assignments are related to object group collections. A change trigger is stored at an explosion update trigger table. The change trigger is stored synchronously with updating definitions of the object group collections and/or updating the hierarchy organization. The explosion update trigger table is processed to determine changes for the explosion table. The change trigger may be processed together with one or more other triggers associated with the object group. The explosion table is updated to reflect changes to the object group and other object groups hierarchically inherent for the object group.