Nonetheless, it is highly useful to provide a means whereby a conceptual row may be removed from a table. In MIB-II, this was achieved by defining, for each conceptual row, an integer-valued columnar object. If a management station sets the value of this object to some value, usually termed "invalid", then the effect is one of invalidating the corresponding row in the table. However, it is an implementation-specific matter as to whether an agent removes an invalidated entry from the table. Accordingly, management stations must be prepared to receive tabular information from agents that corresponds to entries not currently in use. Proper interpretation of such entries requires examination of the columnar object indicating the in-use status.