The relationship between the business layer and the underlying data access layers is considered. The disadvantages of the traditional approach based on the relational database and the data access layer (DAO/ORM) are analyzed. A document-oriented database with built above it an object-oriented network model of data presentation is proposed. The integration with the business layer, automatic assembly of business objects using Java reflection without additional specifications, polymorphic storage and transfer of business entities in collections of the document-oriented database is supported.