LOQIS - THE OBJECT-ORIENTED DATABASE PROGRAMMING SYSTEM

LOQIS is a high-level, object-oriented database programming system designed for the development of "intelligent" applications, such as teaching software, presentation systems and expert systems. It is implemented as a commercial product for personal computers. LOQIS fulfils modern ideas, such as conceptual data view and processing, support for linked, complex objects, no static or dynamic limitations concerning the structure and size of objects, identity of objects independent of their values and locations, late binding time, computational completeness, persistence, encapsulation, and inheritance. The basic constructs of the LOQIS language are non-procedural queries. The query language employs the "many-paths" navigation in a network data structure and has full computational power (including arithmetics and transitive closure). Queries are parameters of commands enabling updating, input, output, and other processing. Owing to queries, the commands accomplish a quasi-parallel (many-data-at-a-time) processing. Procedures and functions are sequences of commands. A function may return a complex value (a relation over atomic values and/or data identifiers). Procedures, functions and data are encapsulated into modules, resembling Modula-2. The inheritance mechanism allows modules to inherit properties from other modules (multi-inheritance). This mechanism may also be applied to data: attributes of data objects may be inherited by other data objects. LOQIS supports a full programming environment (including program editing, data editing, browsing, testing of programs and data, etc.) and is integrated with many technical utilities such as menu windows, high resolution graphics, and hypertext.