Real-time processing behavior depends on the real-time source. Exceptions are noted in this chapter or are described in the corresponding product documentation.
You can use PowerCenter to process data in real time. Real-time processing is on-demand processing of data from real-time sources. A real-time session reads, processes, and writes data to targets continuously. By default, a session reads and writes bulk data at scheduled intervals unless you configure the session for real-time processing.
To process data in real time, the data must originate from a real-time source. Real-time sources include JMS, WebSphere MQ, TIBCO, webMethods, MSMQ, SAP, web services, and PowerExchange. You might want to use real-time processing for processes that require immediate access to dynamic data, such as financial data.
To understand real-time processing with PowerCenter, you need to be familiar with the following concepts:
. Real-time data includes messages and messages queues, web services messages, and changes from a PowerExchange change data capture source. Real-time data originates from a real-time source.
. A real-time session is a session that processes real-time source data. A session is real-time if the Integration Service generates a real-time flush based on the flush latency configuration and all transformations propagate the flush to the targets. Latency is the period of time from when source data changes on a source to when a session writes the data to a target.
. Real-time properties determine when the Integration Service processes the data and commits the data to the target.
. Terminating conditions determine when the Integration Service stops reading data from the source and ends the session if you do not want the session to run continuously.
. Flush latency determines how often the Integration Service flushes real-time data from the source.
. The commit type determines when the Integration Service commits real-time data to the target.
. If the real-time session fails, you can recover messages. When you enable message recovery for a real-time session, the Integration Service stores source messages or message IDs in a recovery file or table. If the session fails, you can run the session in recovery mode to recover messages the Integration Service could not process.