 rdf_journal_file(?DB, 
?JournalFile)True if
File is the absolute file name of an existing named graph
DB. A journal file contains a sequence of Prolog terms of the 
following format.4Future versions 
of this library may use an XML based language neutral format.
rdf_journal_file(?DB, 
?JournalFile)True if
File is the absolute file name of an existing named graph
DB. A journal file contains a sequence of Prolog terms of the 
following format.4Future versions 
of this library may use an XML based language neutral format.
- start(Attributes)
- Journal has been opened. Currently Attributes contains a term time(Stamp).
- end(Attributes)
- Journal was closed. Currently Attributes contains a term time(Stamp).
- assert(Subject, Predicate, Object)
- A triple {Subject, Predicate, Object} was added to the database.
- assert(Subject, Predicate, Object, Line)
- A triple {Subject, Predicate, Object} was added to the database with 
given Line context.
- retract(Subject, Predicate, Object)
- A triple {Subject, Predicate, Object} was deleted from the database. 
Note that an rdf_retractall/3 
call can retract multiple triples. Each of them have a record in the 
journal. This allows for‘undo’.
- retract(Subject, Predicate, Object, Line)
- Same as above, for a triple with associated line info.
- update(Subject, Predicate, Object, Action)
- See rdf_update/4.
- begin(Id, Nest, Time, Message)
- Added before the changes in each database affected by a transaction with 
transaction identifier log(Message). Id is an 
integer counting the logged transactions to this database. Numbers are 
increasing and designed for binary search within the journal file.
Nest is the nesting level, where‘0’is a toplevel 
transaction.
Time is a time-stamp, currently using float notation with two 
fractional digits. Message is the term provided by the user 
as argument of thelog(Message)transaction.
- end(Id, Nest, Others)
- Added after the changes in each database affected by a transaction with 
transaction identifier log(Message). Id and Nest 
match the begin-term. Others gives a list of other databases 
affected by this transaction and the Id of these records. The 
terms in this list have the format DB:Id.