This reference contains a complete description of the Oracle Continuous Query Language (Oracle CQL), a query language based on SQL with added constructs that support streaming data. Using Oracle CQL, you can express queries on data streams to perform event processing using Oracle Event Processing. Oracle CQL is a new technology but it is based on a subset of SQL99.

Oracle Event Processing (formally known as the WebLogic Event Server) is a Java server for the development of high-performance event driven applications. It is a lightweight Java application container based on Equinox OSGi, with shared services, including the Oracle Event Processing Service Engine, which provides a rich, declarative environment based on Oracle Continuous Query Language (Oracle CQL) - a query language based on SQL with added constructs that support streaming data - to improve the efficiency and effectiveness of managing business operations. Oracle Event Processing supports ultra-high throughput and microsecond latency using JRockit Real Time and provides Oracle Event Processing Visualizer and Oracle Event Processing IDE for Eclipse developer tooling for a complete real time end-to-end Java Event-Driven Architecture (EDA) development platform.


This document is intended for all users of Oracle CQL.

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Syntax Diagrams

Syntax descriptions are provided in this book for various Oracle CQL, SQL, PL/SQL, or other command-line constructs in graphic form or Backus Naur Form (BNF). See "How to Read Syntax Diagrams" in the Oracle Database SQL Language Reference for information about how to interpret these descriptions.