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In order to make up the real-time performance of tracking and control information database, this paper design a kind of two-layer’s real-time data storage model based on memory database and relational database. In this article, the two-layer’s real-time data storage mechanism and life cycle are expounded in detail, analyzing and inducing the real-time data characteristic and storage strategy, putting forward the memory database’s self-adaptive index algorithm of T-tree index and hash index, and introducing the database synchronization mechanism between the memory database and relational database and so on. In this way, so as to improve and optimize the real-time, reliability and security of database, provides a reliable data guarantee for future expansion of the real-time application.

University educational management system is the core part of digital campus, this paper uses Oracle 11g database to study the educational management system, Oracle database performance directly impacts on the performance of management system, so the Oracle performance optimization is more and more attention to, the database performance optimization begins from the database design stage, through the database deployment stage and SQL realize process's optimization, to realize university educational management system Oracle database performance optimization goals.

The design of data mining system in database is researched. Vast amounts of information contained in the database, and the data show the diversity of characteristics, resulting in lower efficiency of data mining in database, which database brought greater difficulties to information query. To avoid these shortcomings, database performance optimization method based on cloud computing is proposed. The model of cloud computing data relationship is established to describe the connection between related data inthe database, thus providing the basis for data query. The load state of data nodes is calculated to enable rapid information inquiryin the database. Experimental results show that using this algorithm to optimize data inquiry in database can improve the efficiency of informationinquiry indatabase effectively.

In order to query and manage the graphic files efficiently, and improve the graphic management system in the enterprises, based on the research of dwg、dxf formats, using VC++6.0 language, the graphic title bar information database was created in the Access. With the ODBC interface connected to the graphic database, the preview and query of the graphic database were realized with ActiveX technology. By designing and programming good interactive interface, graphics could be modified and translated conveniently as well as updating the database etc. Simultaneously, by setting identification, the security management of the graphic database was realized. Ultimately, the delivery of enterprises was highly improved.

the computer database has been widely used, it refers to is stored in the computer, data are formed in order to achieve a certain purpose, the construction and maintenance requires high technical content, so you need to improve relevant management personnel's quality, attach importance to database users of technical training, to ensure the good operation of database. From the database design, database, network building, computer database management, database maintenance and so on several aspects of the database construction and maintenance management related issues were studied.

With the transaction processing, data query, location query and other functions of mobile devices, the demand for mobile database has also increased. The analysis of the agent-based mobile database structure and the deficiencies of existing systems provide the basis for future research..

Database technology is one of core technology modules of the computer, mainly including the query of the database, table and database table, safety management, daily management and data transmission, user view and other operation procedures, SQL Server procedure, functions, stored procedure, trigger and other design procedures. With the platform of SQL Server 2008, combined with the basic elements of the database technology, aiming at the demand to cultivate IT talents, relying on the enterprise’s demand on IT job skill, new database technology module architecture is developed in the paper. The structure can provide a good reference value to cultivate new vocational IT talents.

In order to reform the shortcomings of common database with a slower access speed and lower security level, this paper applied sector operating directly instead of general file access, and used the distributed computing and clustering techniques to form an information server cluster as the special database system. Firstly, the layout and sector segmentation methods were provided for data access in sector based database. And then some management methods were given to control information servers in the cluster. Finally, to more efficiently schedule the tasks for storing data and querying information, a dynamic and self-adaptive scheduling algorithm was introduced into the application server of cluster. The practice shows that the system developed by this design strategy has good efficiency and security, and the access speed of the special database system is almost 25 times than that of common database.

Database technology is one of the fastest growing areas of computer science, is also one of the most widely used technology, it has become the core of the computer information system and application system technology and the important basis. In this paper, we discuss all the important aspects of database design process, including requirements analysis phase; The conceptual design stage; The logical design phase; The physical design phase; Database implementation stage; Database operation maintenance phase six stages, and puts forward various problems occurred in the database design, and a variety of ways to solve these problems were analyzed.

Using the geophysical field data matching navigation could improve the concealment of the underwater vehicle, and it is also an important navigation technology in the future. Using the database to save the navigation data not only could overcome the drawbacks when using the files to storage the data but also integrated the different database together. The QNX Database is used to be the database management system (DBMS) of the INS/Database matching navigation system. According to the needs of the INS/Database matching navigation system and the relationship of the geophysical field data, the structure of geophysical field data database is designed and implemented. The result shows that the DBMS has well real-time performance, reliability and scalability. It meets the requirements of the DBMS.

This paper compares different levels of database normalization process in terms of anomalies removal and storage reduction. Several databases have been normalized up to Third Normal Form (1NF, 2NF and 3NF) in order to investigate the influence of the normalization on the database performance. They are implemented separately with different database systems such as MS Access, SQL Server and Oracle. The percentage of storage reduction and data anomalies are investigated for every normal form and database system. The results show that the data storage is significantly reduced over unnormalized database, approximately between 20 to 30% for 1NF flattening tables and 1NF decomposing table, and between (15% - 22%) and (9% - 22%) for 2NF and 3NF, respectively. The removal of the majority of anomalies is observed in the first normal form while fewer anomalies are removed in the next higher normal forms. For the same database implemented, the comparison between three different database systems shows approximately the same results with slight differences. These differences may be due to the nature, the size of the constraints and metadata on each database system.

Realization of big Deep Web database optimized access with low sample deviation was researched. With the sharp increasing of the storage of Deep Web database geometrically, the problem of optimized access to the database was becoming difficult. On the basis of correlation feature rule extraction, an improved optimized access method for the Deep Web database was proposed based on Graph Model Sample process and correlation rule. The access was realized by computer simulation. The access process was started with the arbitrary effective result as the access starting line. The access result was returned, and the records were obtained in the returned web page. The next query and access was implemented with the local sample database for the nest access start line. The method avoided the effects of the query interface properties. And the Graph Model Sample method could overcome the limitation of the query interface properties. Also the correlation feature extraction algorithm was researched, and it was used as the access rule in the database for the realization of optimized and efficient query. The simulation result shows that the sample deviation is stable with the value about 10% for the simulated Deep Web database. The relevant sample deviation value is trended to convergence and is near to the real value with the increasing of the access number. According to the realistic Web database, the sample bias estimation mean value is about 21% which is higher than the simulated database. Two typical Deep Web databases are taken as the researching objects, with the new method, and the access bias is lower than another Web database which without using the proposed method, result shows nice performance of the proposed optimized database access method in application.

The data synchronous of the distributed heterogeneous database was one of the important researches for the heterogeneous databases. This paper analyzed the data synchronization optimization mechanism of the distributed heterogeneous database and puts forward to get the minimum change data set from each node database and then get the system total change data set, and then find out each node database of minimal update data set to update each node database, so as to realize the synchronization of heterogeneous database.

In order to make the real time database more suitable for the computing features in power system, this paper will study the design and architecture of distributed and parallel real-time database. A mapping table from table file to machine nodes is established, and meta-data management system is used to store and manage the mapping table to meet the characteristics of high concurrent access. The whole network computation can access the unified interface provided by the real-time database. The data is retrieved and collected through each node. Experimental results show that the systems designed can meet the computing requirements of a unified whole network.

In order to make the real time database more suitable for the computing features, this article points to the distributed and parallel real time database design and architecture. First, a mapping table from table file to machine nodes is established, and then can use meta-data management system to store and manage the mapping table to meet the characteristics of high concurrent access. The whole network computation can access the unified interface provided by the real-time database, retrive data from each node, then collect the data. Experimental results show that this study and the systems designed can meet the computing requirements of a unified whole network.

Database system is information aggregation. So the security of database is very important. This paper describes the research process of tracking SQL server database data tampered. Now we can monitor the important data in daily work. And providing a guarantee for the safety, accuracy of database.

Based on the remaining research results of database and its development software, this article develops the database system of geotechnical engineering exploration for a city using the database management system SQL Server 2005 and vb6.0, and establishes the database tables at all levels, and then advances the more reasonable System Structure, which make the system realize data edition function, information inquiry function, database management function, graph drawing function, data output function and so on. Moreover, the system interface is friendly and the system is easy to operate so that it is convenient for users to study and use, and it achieves good results.

During processing database query or dealing with huge amounts of data, the conventional query method is not only a waste of resources but also may perform repeated or useless operations which may cause the database overburdened even. For solving the problem of time-consuming in conventional database query, this paper presented a more convenient solution to the problem in conventional database queries. This paper constructed an XML document to simulate the database and transformed the database query into the XML queries. Experiments showed that speed can be significantly improved for database query and better results can be obtained.

Database query optimization is a very complicated issue, also is the key influencing factor in database systems performance. Database query operation efficiency is one of the key factors that affect system response time. Therefore, how to improve the efficiency of database query system becomes particularly important. This paper, on the basis of the advantages of Quantum particle swarm optimization algorithm, proposes distributed database query optimization methods based on Quantum particle swarm optimization algorithm, and improves algorithm. Simulation comparison experiments show that Quantum particle swarm optimization algorithm can improve the efficiency of the distributed database query, and is an effective way to solve the optimization of distributed database query.

This article using three kinds of storage structure combined to store field data, that is memory database, relational database and document management system. This paper also gives the basic realization scheme of real-time database, and using Windows dynamic link library technology and the global shared memory technology to establish real-time database system.

Through the in-depth study of the existing distributed database query processing technology, this paper proposes a distributed database query processing program. This program optimizes the existing query processing, stores the commonly used query results according to the query frequency, to be directly used by the subsequent queries or used as intermediate query results, thus avoiding possible transmission of a large number of data, thereby reducing the query time and improving query efficiency.

The distributed database system is the product that the database system combines with the computer network system. The data distribution problem has great influence on distributed database application system improvement, data availability, the efficiency and reliability of the distributed database. The allocation strategies in this paper have used some excellent properties in genetic algorithms, including higher parallelism and robustness, the realization of standard way, and to maintain good balance between the depth prior search and breadth prior search, etc, so the allocation strategies in this article's have high execution efficiency, with stronger ability in seeking the best global solution and easy to realize.

For automated testing system to manage harvesting data requirements, the paper discusses the method of using the tool of LabSQL database access to visit access database on LabVIEW programming circumstances, and gives an example of specific database management in data collection of application. The system communicated with fieldbus and based on VISA programming interface, acquisition to obtain multi-channel sensor signals. Reusing database technology to realize data query, backup, import management functions for the detection system collection income amount of data convenient and effective. This system has been applied in a automated testing system.

With the rapid development of computer technology, database technology is becoming an important branch of the computer field, it is increasingly being used in e-commerce, Web services, information systems, etc., database technology research has become necessary. This paper describes the development process of database technology, and then lists a number of measures to optimize database performance, and finally on the future development trend of the database are discussed.

Based on the analysis of web database realize technique,the paper researches the design of the web database system by JSP. aim at the problem that database access based on JDBC is low efficiency in distribute servers, one of the solutions is adopting the method of database connection pool. and completes the network information management system based on Browser/server(B/S) mode.

Access control is the process of mediating every request to data and services maintained by a system and determining whether the request should be granted or denied. Access control policies are security policies that govern access to resources. It can be applied to several new types of databases. LogicSQL is an object relational database management system implemented with the advanced (formula-lock based) concurrency control protocol, and the steged database architecture. In this paper, we discuss access control in multilevel database management systems applies and illustrate the main applies of access control in the LogicSQL database system.

In this paper, we take Oracle as the example of relational database, and Caché as a post-relational database. We implement the performance test between relational database and post-relational database in HIS. The results prove post-relational are much more efficient than relational database.