  In the paper a new approach to data representation and manipulation is
described, which is called the concept-oriented data model (CODM). It is
supposed that items represent data units, which are stored in concepts. A
concept is a combination of superconcepts, which determine the concept's
dimensionality or properties. An item is a combination of superitems taken by
one from all the superconcepts. An item stores a combination of references to
its superitems. The references implement inclusion relation or attribute-value
relation among items. A concept-oriented database is defined by its concept
structure called syntax or schema and its item structure called semantics. The
model defines formal transformations of syntax and semantics including the
canonical semantics where all concepts are merged and the data semantics is
represented by one set of items. The concept-oriented data model treats
relations as subconcepts where items are instances of the relations.
Multi-valued attributes are defined via subconcepts as a view on the database
semantics rather than as a built-in mechanism. The model includes
concept-oriented query language, which is based on collection manipulations. It
also has such mechanisms as aggregation and inference based on semantics
propagation through the database schema.
