dQUOB (Dynamic QUery OBjects) targets run-time analysis of complex, interactive scientific applications for purposes of attaining scalability improvements with respect to the amount and complexity of the data transmitted, transformed, and shared among different application components. Such improvements are derived from using database techniques to manipulate data streams. Namely, by imposing a relational model on the data streams, constraints on the stream may be expressed as database queries evaluated against the data events composing the stream.

dQUOB (1) offers the means for dynamic creation of queries and for their application to large data streams, (2) permits implementation and runtime use of multiple ‘query optimization’ techniques, and (3) supports dynamic reoptimization of queries based on streams’ dynamic behavior.

Inter-node communications and coordination of query I/O within nodes is done via embedded Tcl interpreters.