status of the object is reset to something compatible with the environment the attribute setting must be asimple assignment since on the one hand it must not depend on other objects they are the ones causing problems and on the other hand must not fail since there is no 34 old value 34 to return to removal of reference this is the normal way to act with references to objects not existing this is suitable in case of optional references which have disappeared but may also be usable in case of cardinality errors or even state errors removal of the object this can be suitable in case of existence dependency or possibly in case of cardinality dependency if the object is removed there is no reason to use any of the two actions mentioned above send a notification to some agent this action may be used e g if it is desirable to inform operators or similar if the object is locked by some other transaction locked is returned if the object is not open it is opened with write lock in tr and if it hasnot ok flag set it effects verify tr on it self possibly existingerror codes are returned otherwise check tr of the self object is called and error codes or a ready are returned if the object is open and is busy verifying it self i e rec statusis verifying self or must check rec status.