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erase(+DBRef)
Succeeds if the database reference DBRef designates a term recorded in the
record database and this term is successfully erased.
- DBRef
- A database reference.
Description
   The database reference DBRef must refer to a term that has been recorded
   in the record database.  Database references can be obtained from the
   predicates recorda/3, recordz/3 and recorded/3.  If the referenced term
   has already been erased, erase/1 fails.  Backtracking through calls of
   erase/1 does not undo an erasure.  Note that an erased term can still
   be retrieved via the database reference, but it can no longer be found
   by lookup under the recording-key.
Modes and Determinism
Fail Conditions
Fails if DBRef refers to an already erased record
Exceptions
- (4) instantiation fault 
- DBRef is not instantiated.
- (5) type error 
- DBRef is not a database reference.
Examples
   Success:
   [eclipse]: recordz(whiskey, jameson, _),
   recordz(whiskey, glenfiddich, Ref),
   recordz(whiskey, dimple, _),
   erase(Ref).
   Ref = $&(dbref,"370h9z")
   yes.
   [eclipse]: recorded(whiskey, L, _).
   L = jameson     More? (;)
   L = dimple     More? (;)
   no (more) solution.
   Fail:
   [eclipse]: recorded(whiskey,_,R), !, erase(R), erase(R).
   no (more) solution.
   Error:
   erase(Var).                            (Error 4)
   erase(123).                            (Error 5)
See Also
erase_all / 1, is_handle / 1, recorda / 3, recordz / 3, recorded / 3, referenced_record / 2