A Continuous Query Processor processes queries on continuously updating
data sources or data streams and includes a Publication Manager for
accepting published structured elements of data from data stream
Publishers, a Subscription Manager for giving structured elements of data
to one or more data stream Subscribers, a Query Module Manager for
processing queries represented by Query Modules, a Query Module Store for
maintaining deployed Query Modules, a Query Primitive Manager performing
processing for various primitives that comprise a Query Module, and a
Schedule Manager for coordinating when a primitive within a Query Module
gets processed in order to maintain that each continuous query is
continuously updated immediately upon the arrival of structured element
data affecting any part of a continuous query.