Channels as Streams Channels Representing Streams and Relations

9-6 Oracle Complex Event Processing Developers Guide

9.1.6 Batch Processing Channels

By default, a channel processes events as they arrive. Alternatively, you can configure a channel to batch events together that have the same timestamp and were output from the same query by setting the wlevs:channel attribute batching to true as Example 9–7 shows. Example 9–7 Batch Processing Channel ... wlevs:channel id=priceStream event-type=PriceEvent batching=true wlevs:listener ref=filterFanoutProcessor wlevs:source ref=PriceAdapter wlevs:channel ... For more information, see: ■ Section 1.1.3.2, Stream and Relation Sources ■ Section 1.1.3.3, Stream and Relation Sinks ■ batching in Table C–9, Attributes of the wlevs:channel Application Assembly Element

9.1.7 EventPartitioner Channels

By default, a channel broadcasts each event to every listener. When you configure a channel to use an EventPartitioner, each time an incoming event arrives, the channel selects a listener and dispatches the event to that listener instead of broadcasting each event to every listener. You can use an EventPartitioner on a channel to improve scalability. For more information, see Section 22.2.1, EventPartitioner .

9.2 Configuring a Channel

You can configure a channel manually or by using the Oracle CEP IDE for Eclipse. See Section B.2, Component Configuration Schema wlevs_application_config.xsd for the complete XSD Schema that describes the channel component configuration file. See Section 9.3, Example Channel Configuration Files for a complete example of a channel configuration file. This section describes the following topics: ■ Section 9.2.1, How to Configure a System-Timestamped Channel Using Oracle CEP IDE for Eclipse ■ Section 9.2.2, How to Configure an Application-Timestamped Channel Using Oracle CEP IDE for Eclipse ■ Section 9.2.3, How to Create a Channel Component Configuration File Manually

9.2.1 How to Configure a System-Timestamped Channel Using Oracle CEP IDE for Eclipse

This section describes how to create a system-timestamped channel.