The Research Of Embedded Database System Suitable For Industrial Control

With the development of the embedded technology, the embedded system needs to manage more and more data. Now the research about the embedded database has become an active research topic.In this paper we focus on the embedded database system used in the industrial control application. In the industrial control systems, it not only require the embedded database to have datum managerial ability like the traditional database , but also require there can be certain real-time character in the embedded database system. This paper combine the characteristics of industrial control, real-time embedded system, and database system, understanding the inner link between the three aspects, to study the design and implementation technology of the embedded database system.This paper present two issues of integrating an embedded real time database system into the real-time industrial control system. Firstly the database should support real-time transactions, secondly the database should satisfy the access to the hot data. The traditional database uses the index to access data. However the drawback with the data management systems is the overhead added when accessing data by index system in high frequency. This paper present a new concept named database pointers, which provides fast and deterministic accesses to data in real-time database management systems without the need of consulting the indexing system,and the database pointer is suitable for the access to the hot data by numerous small control tasks running at high frequencies.This paper also make a detailed analysis and compare to the implementation technique of the embedded database, including the database model, data model, index system, database interface, concurrency control etc.On the aforesaid foundation of analysing and discussing, this paper development a mixed real-time embedded database system —MRTEDBS, which is suitable for industrial contorl. The MRTEDBS supports both soft and hard real-time transactions. It uses the relational transaction interface to deal with the soft real-time transactions, and uses the database pointer to deal with the hard real-time transactions.