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recorda(+Key, ?Value, -DBRef)

Records the term Value at the beginning of key Key in the indexed database.
Key
An atom, compound term, or handle.
Value
Any prolog term.
DBRef
A variable.

Description

Used to record any prolog term Value at the beginning of the indexed database entry associated with the key Key. Unlike recorda/2, this predicate delivers a so-called database reference in DBRef which is a unique handle for the indexed database entry that is created. In the case of compound terms, all keys of the same name and arity are treated as equal.

If backtracking occurs through the call of recorda/3 the associated Value is not removed from the indexed database.

Modes and Determinism

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Exceptions

(4) instantiation fault
Key is not instantiated.
(5) type error
Key is neither an atom nor a compound term.
(5) type error
DBRef neither a variable nor a database reference.

Examples

   Success:
    [eclipse]: recorda(whiskey,jameson,Ref1),
             recorda(whiskey,bushmills,Ref2).
    Ref1 = 'DBREF'(16'50470dc8)
    Ref2 = 'DBREF'(16'50470de0)
    yes.
Error:
    recorda(Key, anything, Ref).          (Error 4)
    recorda("key",anything, Ref).         (Error 5)
    recorda(key,anything, 99).            (Error 5)



See Also

recordz / 3, recorded / 3, is_handle / 1, erase / 1, referenced_record / 2