1. A computer-implemented method comprising: providing a database comprising a core data services (CDS) component including a data definition language (DDL) compiler and overlying a lower layer organized according to a relational model and including a first table comprising a base artifact; providing a database engine in communication with the database utilizing a data definition language describing the relational model and including a structural extension element associating the first table with a second table; providing an application comprising an entity-relationship model including the second table; a query engine communicating a query to the database engine utilizing an extended query language accommodating the entity-relationship model, the extended query language comprising an alias; the DDL compiler referencing the alias to uniquely identify that the structural extension element is referenced by the query, and the database engine returning a query result including data from the first table to the query engine based upon the extended query language.