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3.10. Programmatic Control

Red Hat JBoss Data Virtualization exposes a bean that implements the org.teiid.events.EventDistributor interface. You can find it in JNDI under the name teiid/event-distributor-factory. The EventDistributor exposes methods like dataModification (which affects result set caching) or updateMatViewRow (which affects internal materialization) to alert the Teiid engine that the underlying source data has been modified. These operations, which work cluster wide will invalidate the cache entries appropriately and reload the new cache contents.

Note

If your source system has any built-in change data capture facilities that can scrape logs, install triggers and so forth to capture data change events, they can captured and can be propagated to the Teiid engine through a pojo bean/MDB/Session Bean deployed in the Red Hat JBoss EAP engine.
This code shows how you can use the EventDistributor interface in their own code that is deployed in the same JBoss EAP virtual machine using a Pojo/MDB/Session Bean: 
  
   public class ChanageDataCapture {
 
    public void invalidate() {
        InitialContext ic = new InitialContext();
        EventDistributor ed = ((EventDistributorFactory)ic.lookup("teiid/event-distributor-factory")).getEventDistributor();
 
        // this below line indicates that Customer table in the "model-name" schema has been changed.
        // this result in cache reload.
        ed.dataModification("vdb-name", "version", "model-name", "Customer");
    }
}

Important

The EventDistributor interface also exposes many methods that can be used to update the costing information on your source models for optimized query planning. Note that these values are volatile and will be lost during a cluster re-start, as there is no repository to persist.