1. A computer-implemented method of processing streams of data using continuous queries, the method comprising: receiving an instruction to delete a first continuous query; deleting a second continuous query on which is built a view referenced by the first continuous query, if said view is not referenced by any continuous query other than the first continuous query; compiling the second continuous query, in response to said deleting; and updating said view to refer to a newly-compiled version of the second continuous query, in response to said compiling.