@MASTERSTHESIS\{IMM2005-03857,
    author       = "M. Johnsen",
    title        = "High Level Database Interface with Application to {GIS}",
    year         = "2005",
    school       = "Informatics and Mathematical Modelling, Technical University of Denmark, {DTU}",
    address      = "Richard Petersens Plads, Building 321, {DK-}2800 Kgs. Lyngby",
    type         = "",
    note         = "Supervised by Professor J{\o}rgen Fischer Nilsson and Associate Professor Hans Bruun",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/3857-full.html",
    abstract     = "This thesis presents a high level language hlcl (High Level Constraint Language) which facilitates the formulation of constraints imposed on a relational database. The language has been designed with a syntax very similar to natural language and has been developed to be as intuitive as possible. It is based on the so-called  Peirce Product  known from algebraic logic, which gives clear and unambiguous semantics. The language is intended to help trained domain specialists, who are not necessarily logic specialists, formulate constraints correctly.

Constraints are formulated in hlcl on the basis of a conceptual model (E/R-diagram), which has a specified map into the actual database schema. The specification of the conceptual model, database schema and the mapping between the two are referred to as the database model.

The thesis also describes a compiler system, which given a database model can compile constraints formulated in hlcl to a directly executable sql query and well-defined datalog interface. A proof-of-concept compiler system is implemented in prolog and tested with actual constraints from the Geographic Information Domain."
}