In some cases, we might be inserting rows using null for values that are not specified, and even though our intention is to leave the value empty, Cassandra will represent it as a tombstone causing an unnecessary overhead. To avoid tombstones, in previous versions of Cassandra, you can use different query combinations only containing the fields that have a value.

The Unset type is a singleton class, which means only one Unset object exists. The Unset.Value member represents the sole Unset object.