Column-oriented database systems have been a real game changer for the industry in recent years. Highly tuned and performant systems have evolved that provide users with the possibility of answering ad hoc queries over large datasets in an interactive manner.In this paper we present the column-oriented datastore developed as one of the central components of PowerDrill 1 . It combines the advantages of columnar data layout with other known techniques (such as using composite range partitions) and extensive algorithmic engineering on key data structures. The main goal of the latter being to reduce the main memory footprint and to increase the efficiency in processing typical user queries. In this combination we achieve large speed-ups. These enable a highly interactive Web UI where it is common that a single mouse click leads to processing a trillion values in the underlying dataset.

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The problem of providing connectivity for a collection of applications is largely one of data integration: the communicating parties must agree on the semantics and syntax of the data being exchanged. In earlier papers, it was proposed that dictionaries of de nitions for operators, functions, and symbolic constants can e ectively address the problem of semantic data integration. In this paper we extend that earlier work to discuss the important issues in data integration at the syntactic level and propose a set of solutions that are both general, supporting a wide range of data objects with typing information, and e cient, supporting fast transmission and parsing.

Monomial representations and operations for Gr obner bases computations are investigated from an implementation point of view. The technique of vectorized monomial operations is introduced and it is shown how it expedites computations of Gr obner bases. Furthermore, a rank-based monomial representation and comparison technique is examined and it is concluded that this technique does not yield an additional speedup over vectorized comparisons. Extensive benchmark tests with the Computer Algebra System Singular are used to evaluate these concepts.

About IDSThe Institute of Development Studies is one of the world's leading charities for research, teaching and communications on international development. Founded in 1966, the Institute enjoys an international reputation based on the quality of its work and the rigour with which it applies academic skills to real world challenges. Its purpose is to understand and explain the world, and to try to change it -to influence as well as to inform.IDS hosts five dynamic research programmes, five popular postgraduate courses, and a family of worldclass web-based knowledge services. These three spheres are integrated in a unique combination -as a development knowledge hub, IDS is connected into and is a convenor of networks throughout the world.The Institute is home to approximately 80 researchers, 50 knowledge services staff, 50 support staff and about 150 students at any one time. But the IDS community extends far beyond, encompassing an extensive network of partners, former staff and students across the development community worldwide.