Stream data is processed according to the instructions in the query definition file used by the system. The query definition file uses CQL to describe the stream data type (STREAM) and the queries. These CQL instructions are called CQL statements.
There are two types of CQL statements used for writing query definition files:
This section describes how to use definition CQL to define streams and queries, and how to use data manipulation CQL to perform processing on stream data.
For additional details about CQL, see the uCosminexus Stream Data Platform - Application Framework Application Development Guide.
CQL statements consist of keywords, which have preassigned meanings, and items that you specify following a keyword. An item you specify, combined with one or more keywords, is called a clause. The code fragments discussed on the following pages are all clauses. For example, REGISTER STREAM stream-name, consisting of the keywords REGISTER STREAM and the user-specified item stream-name, is known as a REGISTER STREAM clause.