INVESTIGATION AND DEVELOPMENT OF LANGUAGE SUBSYSTEM FOR SQL SERVER

The generation technology of the imperative code has been developed. Within its frames the tool-independent homogeneous representation permitting to work out the procedure plan of imperating operators in the early compiler phases is used. In its turn, each of phases can be constructed as a connected set of the conversion rules. The up-to-date set of the optimization methods including the simplifying semantic conversions of the queries and algorithms for choice of the effective plan has been put into system as conversion rules. The virtual machine of the effective system has been developed. The command system of the virtual machine permits the direct code generation from SQL-similar representation and gives a possibility to retain the invariants inner scanning cycles without power loss. The comparative-simple code layer of the virtual machine permits to adapt the system to the changes in the effective system of DBMS. The system of the commands follows to the object model. The different type of the scanners both the base class and different variants of the generated ones are considered as examples of the objects generated by a compiler. The tool for operation with the intermediate representation trees have been developed also. It permits to describe, recognize and convert these trees by a natural way (in the Lisp style) within the frames of the C-programs. The conversion rules of the SQL operators are given in the system on base of this tool. The implemented package (DBMS) is in the beta-testing stage, is used at the Moscow State University and Moscow Engineering-Physical Institute and accessible on the servers of the Institute of System Programming, Russian Academy of SciencesAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio