The Design And Implementation Of Database Server Of Seafloor Observatory Network

As an important component of the control and management system of Shore-Side station, the database server of seafloor observatory network is not only the link between the user and marine equipments, but also the data exchange and storage center of the entire seafloor observatory network. On the basis of learning experiences on data transmission and management from the monitoring and controlling System at home and abroad, this paper analyses the basic functions which the database server should have, such as network communication, data analysis, data storage and data maintenance, for the actual situation of the Seafloor Obsevatory Network experimental prototype node. According to that, the Server is designed and implemented.Firstly, the SQL relational database is selected to store data and datasheets in the database are designed into two parts including "public table" and "log table". The public table is used to store relatively static property of the entities and the log tables which are dynamicly created by the server program at the specified time each day is used to store observing data collected by equipments.Secondly, according to the functional requirements of the database server, the sever program is designed and implemented. The server program is composed of three modules including network communication, data analysis and storage, data maintenace. The communication packets are designed and the integrity of the data during the communication process is maximumly ensured by taking the "question and answer" method of communication, packet number and checksum defined by ourselves. Using completion port and overlapped I/O model provided by winsock network communication mechanism, the server achieves TCP communication with lower computers efficiently. In addition, the IP detection function is coded to prevent malicious link. In data analysis and storage module, mandatory type conversion is enforced for the data in packet and the correct result is got after been calculated, and then the result is stored to the corresponding log table in database. Consistency and integrity during the data maintenance process are ensured by the mechanism of transation and lock, and basic data maintenance operations are achieved such as the addition, deletion and modification to data records, the migration and deletion to datasheets, and so on.Finally, the database server can simultaneously communicate with lower computes in a long time after the tests in pool experiments. The transmission course of the data is steady and the data can be stored into the database completely. The anticipatory target is achieved.