The Research And Realization Of The Embedded Database System

Embedded database management system is blooming in recent years. It implements the convenient and unified data management on embedded devices, integrated the technology of the traditional database management system and the special features of the embedded environment.In the paper, we designed and implemented an embedded database management system (EDB) to manage the data of the mobile device. With the help of the EDB, users can design the PIM(Personal Information Management system) of PDA to manage the business and private data(such as business cards, calender, trip plan, etc) conveniently. The operations of the data such as index etc are also very convenient.Besides the common functions of creating,deleting table, inserting,,deleting,,updating record, doing query etc, the system has some perfect features such as small kernel, size scalable, mufti plat performance, robust and convenient application programming interface, etc.This paper focuses on the design and implementation issues of the embedded database management system, which evolved the details of the embedded database management system theory and the implementation. The discussions of the topics are organized in the following aspects:Firstly, the development and prospect of the embedded database is described in the paper. As a database subsidiary, embedded database has its strong historical background and customer demand. Nowadays with its complete and sophisticated functions, the embedded database becomes more and more popular.Secondly, the paper discusses the theory and implementation methods of the embedded database fundamental functions. This part describes the key technologies of the embedded database storage management, it integrates the data structure knowledge, the embedded system technology and the database technology successfully.And then, this paper studies the key technology of the embedded database: high efficient SQL compiler. After discussed and explained the theory of the SQL comelier implementation, this paper implements a SQL comelier with comprehensive functions, using the tool Lemon.The system is designed with the modules and layers. The database can be divided into the querying,deleting,updating modules etc. Each module is expressed by a process view. We can understand the work process of the SQL by the view. Here we should know the system is implemented by two steps. The first step is to translate the SQL to the corresponding middle code, then the middle code executes the database file by the virtual machine.