A Quasardb batch operation type. Available operations are :
- GET : get an entry.
- PUT : put an entry.
- UPDATE : update an entry.
- REMOVE : remove an entry.
- CAS : atomically compare a value with comparand and update if it matches.
- GET_UPDATE : atomically update the value of an existing entry and return the old value.
- GET_REMOVE : atomically get the entry associated with the supplied key and remove it.
- REMOVE_IF : delete the object associated whith a key if the object is equal to comparand.
- NO_OP : no operation.