A document comprised of structured data represented as sets of relations. These relations are basically sets of tuples (representing entity relationships) grouped by a predicate which indicates the entity relationship type. For instance, in a SQL Relational Database Management system a Table Name functions as the Predicate. Whereas in an RDF Predicate/Property Graph based Relational Database Management system (or store) a Predicate is self-evident part Subject->Predicate->Object based 3-tuple.