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recorded(+Key, ?Value, -DBRef)
Succeeds if the term Value has been recorded in the indexed database under
the key Key and DBRef is its unique reference.
- An atom or a compound term.
- Any Prolog term.
- A variable.
Used to find all values associated with a key. Value is unified with
the first term that is associated with Key. DBRef is unified with the
unique database reference of this database entry. In the case of
compound terms, all keys of the same name and arity are treated as
equal. If Value is instantiated, the instantiated term is used as a
filter to reduce the number of terms returned by the recorded database
and unified with Value, thus improving the speed of retrieving the term.
Backtracking will unify Value and DBRef with the value resp. the
database reference of successive values associated with Key in the order
in which they were recorded.
Modes and Determinism
- recorded(+, -, -) is nondet
- recorded(+, +, -) is nondet
This predicate is sensitive to its module context (tool predicate, see @/2).
Fails if nothing is recorded under the key Key
- (4) instantiation fault
- Key is not instantiated.
- (5) type error
- Key is neither an atom nor a compound term.
- (5) type error
- DBRef is neither a variable nor a database reference.
[eclipse]: recordz(beer, paulaner, _),
recordz(beer, lowenbrau, _),
recorded(beer, Value, Ref).
Value = paulaner
Ref = 'DBREF'(16'50470e90) More? (;)
Value = lowenbrau
Ref = 'DBREF'(16'50470ea8) More? (;)
no (more) solution.
recorded(Beer,Value,Ref). (Error 4)
recorded("beer",Value,Ref). (Error 5)
recorded(1,Value,Ref). (Error 5)
recorda / 3, recordz / 3, erase / 1, is_handle / 1, referenced_record / 2