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 Object-Oriented DataBase Management System  Виталий Шматиков 14.07.1995

Объектно-ориентированная система для управления базами данных формата DBF. Предназначена длч совместной работы с TurboVision.
This package contains a simple OODBMS (Object-Oriented DataBase Management System) for Turbo Pascal 7.0. May be incorporeted into TurboVision applications.


This package contains a simple OODBMS (Object-Oriented DataBase Management System). The list of files: ------------------ README.DOC This file INTFACE.DOC Database interface description DBDEMO.EXE Executable demo OODB.PAS Source code of the database management system DBDEMO.PAS Source code of a simple demo program LAYOUT.PAS Auxilliary routines for the demo OODB.TPU Compiled OODB unit LAYOUT.TPU Compiled LAYOUT.PAS FEATURES --------- OODBMS is intended to be incorporated into TurboVision applications. It maintains a storage of arbitrary objects. The only requirements imposed on objects are that they must be TObject heirs and their Store and Load methods must be registered (by means of standard RegisterType procedure). OODBMS supports transactions. One can "commit" or "abort" database at any moment. Abort returns database to its state just before the last Commit. All objects deleted since then are recalled and all objects put to the database vanish. Any failure that could have occured during the transaction (i.e., group of database operations starting with Commit and ending with Abort or Commit) is annulled and database is rollbacked to its consistent state. When user believes that transaction has been successfully completed he should make all changes permanent by executing Commit. OODBMS performs (at least, tries to perform) intelligent garbage collection. It contains IdlePack method that should be invoked each time after TApplication.Idle routine is called by the user's application. IdlePack fights fragmentation and gets rid of "holes" in the database. Packing is performed "step by step" and can be interrupted at any moment. Generally, database is being packed while user isn't working with application and the process of defragmentation can hardly be noticed "from the outside". ABOUT ------ OODBMS was developed in March - April '92 at the M.V.Keldysh Institute for Applied Mathematics, Moscow, Russia, and at Moscow State University as my student junior year thesis. It is distributed as a freeware. Though it has been debugged and tested, I can't guarantee that the code is bug-free. Everybody is not only allowed but also encouraged to correct bugs, make modifications, distribute this program, etc. There are no limitations whatsoever on the use of this program. In case of commercial use no financial reimbursement is expected either by me or by the Institute for Applied Mathematics. There are also other versions of OODBMS with memory caching and Paradox-based indices respectively. Information about them is available upon request (see address below). I would appreciate if the bugs were reported to me by e-mail (see address below). I would also be very glad if I were contacted by somebody who dealt with these problems and has any proposal for the upgrade of database or just wants to "talk about". Until September '92 I can be accessed at shmat@drew.cog.brown.edu or shmat@browncog.bitnet or Vitaly Shmatikov P.O.Box 1978 Dept. of Cognitive and Linguistic Sciences Brown University Providence, RI 02912 Since October '92 I'll be at the University of Washington, Seattle, WA. Vitaly Shmatikov July 14, 1992