Research Of Weaving Application Based On Log In AODB System

From 1970's when database theory appeared to these years, database technology, together with the development of programming thinking, has never stopped its development. From the level-based database system which appeared earliest, to the relation database system, the object database system appeared with object-oriented technology's appearance and maturation. After the emergence of aspect-oriented programming thinking, at the beginning of this century, the concept of aspect- oriented database appeared.Aspect-oriented programming thinking is an extending and updating of object-oriented programming thinking. It can solve problems as high code overlapping, bad customization and hard maintenance existing in object-oriented software systems. So aspect-oriented database system is consummation and improvement of object-oriented database system. Like other large object-oriented software systems, many crosscutting concerns exist in aspect-oriented database system, and these crosscutting concerns intersperse in Database level and DBMS level. Therefore, introducing aspect-oriented technology into object-oriented database system to construct aspect-oriented database system can make the database system better in modularity, customizability and Maintainability. As an emerging database system framework, aspect-oriented database system is in the stage of theoretical and experimental research these years.This thesis mainly researches the essence, various implementation and superiority of aspect-oriented technology, crosscutting concerns in database system and the weaving and recovery mechanism based on log in aspect-oriented database system. First, researches aspect-oriented technology and methods to separate crosscutting concern in depth; then, discusses crosscutting concerns in Database level and DBMS level of database system from the angle of aspect-oriented. Based on the research above, researches the weaving-on-demand and weaving history mechanisms which are proposed to introduce into building aspect weaver into DBMS, and then, gives a weaving approach implementation based on log. This approach realizes the weaving-on-demand and weaving history mechanisms together with keeping the persistence of aspect. Afterwards, proposes a mechanism of recovering aspect weaving state based on log when aspect-oriented database system restarts normally or abnormally. At last, verify the validity of the mechanism in the condition of whether having log buffer in memory through experiment.