In this letter we analyze the economic worth of GPU on analytical processing of GPU-accelerated database management systems (DBMSes). To this end, we conducted rigorous experiments with TPC-H across three popular GPU DBMSes. Consequently, we show that co-processing with CPU and GPU in the GPU DBMSes was cost-effective despite exposed concerns.

Web APIs are offered in many Web sites for Ajax and mashup, but they have been developed independently since no reusable database component has been specifically created for Web applications. In this paper, we propose WAPDB, a distributed database management system for the rapid development of Web applications. WAPDB is designed on Atom, a set of Web API standards, and provides several of the key features required for Web applications, including efficient access control, an easy extension mechanism, and search and statistics capabilities. By introducing WAPDB, developers are freed from the need to implement these features as well as Web API processing. In addition, its design totally follows the REST architectural style, which gives uniformity and scalability to applications. We develop a proof-of-concept application with WAPDB, and find that it offers great cost effectiveness with no significant impact on performance; in our experiments, the development cost is reduced to less than half with the overhead (in use) of response times of just a few msec.

Access control is a key technology for providing data security in database management systems (DBMSs). Recently, various authorization models for object-oriented databases (OODBs) have been proposed since authorization models for relational databases are insufficient for OODBs because of the characteristics of OODBs, such as class hierarchies, inheritance, and encapsulation. Generally, an authorization is modeled as a set of rights, where a right consists of at least three components s, o, t and means that subject s is authorized to perform operation t on object o. In specifying authorizations implicitly, inference rules are useful for deriving rights along the class hierarchies on subjects, objects, and operations. An access request req=(s,o,t) is permitted if a right corresponding to req is given explicitly or implicitly. In this paper, we define an authorization model independent of any specific database schemas and authorization policies, and also define an authorization specification language which is powerful enough to specify authorization policies proposed in the literature. Furthermore, we propose an efficient access control method for an authorization specified by the proposed language, and evaluate the proposed method by simulation.