Using Esper, How to retrieve data from relational database

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I have followed steps described in http://stackoverflow.com/a/26735420/4022876; but my problem is my listener not receiving any data from database.

My Listener: @Override public void update(EventBean[] newEvents, EventBean[] oldEvents) { LOG.info("Update method call...."+ oldEvents.length); WellProdEvent event = (WellProdEvent)newEvents[0];

LOG.info("Event values...."+ event.getCountyName()); }

Code snippet and install a query in Esper's instance in the following manner:

ConfigurationDBRef dbConfig = new ConfigurationDBRef();
        dbConfig.setDriverManagerConnection("com.mysql.jdbc.Driver",                                                                "jdbc:mysql://localhost:3306/riab",                                        "root", "root");
        dbConfig.setMetadataOrigin(MetadataOriginEnum.DEFAULT);
        dbConfig.setLRUCache(10);
        Configuration engineConfig = new Configuration();
        engineConfig.addEventType("WellProdEvent", WellProdEvent.class);
        engineConfig.addDatabaseReference("database_alias", dbConfig);

        EPServiceProvider esperEngine = EPServiceProviderManager.getDefaultProvider(engineConfig);
        //@Hook(hook = "WellProdEvent", type = HookType.SQLROW)
        String statement =  "SELECT wp.countyName FROM WellProdEvent wp,  "
                + " sql: database_alias[\"SELECT FILE_NO, WELL_DATE, COUNTY_NAME, FILED_NAME, Operator,BBLS_Oil, NO_OF_DAYS "
                + " FROM well_prod_events\"]";
                //+ " WHERE COUNTY_NAME = \'WILLIAMS'\"] AS Res";

        //Install this query in the engine

        EPStatement queryEngineObject = esperEngine.getEPAdministrator().createEPL(statement);              

         LOG.debug("created statement...");
        //Associate a Listener to this query
        EventListener listener = new EventListener(); //that implements UpdateListener Interface
        queryEngineObject.addListener(listener);   

asked 13 secs ago

sgelle

5

Using Esper, How to retrieve data from relational database