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While parallel DBMSs do support large scale parallel query processing on partitioned data, the reach of more general applications relies on User Defined Functions (UDFs). However, the existent UDF technology is insufficient both conceptually and practically. A UDF is not a relation-in, relation-out operator, which restricts its ability to model complex(More)
Mobile applications, such as those on WebOS, increasingly depend on continuous analytics results of real-time events, for monitoring oil & gas production, watching traffic status and detecting accident, etc, which has given rise to the need of providing Continuous analytics as a Service (CaaaS). While representing a paradigm shift in cloud computing,(More)
NonStop Structured Query Language (SQL) is a distributed database management system (DBMS) running on a loosely coupled multiprocessor machine. It allows horizontally partitioned relations. This environment makes it possible to execute larger operations in parallel. The different parallel execution models in NonStop SQL and the underlying process(More)
Research in the area of subquery unnesting algorithms [ 1,2,3,4,5,6] has mostly focused on the problem of making queries more efficient at run-time by transforming subqueries into joins. Unnesting rules describe a transformation of a nested query tree or a nested SQL query into an equivalent tree or SQL query that is no longer nested. However, it is not(More)
Relational queries on continuous streams of data are the subject of many recent database research projects. In 1998 a small group of people started a similar project with the goal to transform our product, NonStop SQL/MX, into an active RDBMS. This project tried to integrate functionality of transactional queuing systems with relational tables and with SQL,(More)