Event based in sender JDBC adapter level...???

I am working on a scenario where need to get the data from Oracle Tables to SAP.

In this Oracle DB we have a staging table.  All the required base table data will be transfered to Staging table.

Once that process completes, we need to get an event from Oracle, based on that we need to activate our Channel so that data will be captured from Oracle tables to SAP.

Please help how an event can be passed from Oracle to SAP PI....????

and more over how can we handle large volumes of Data from Oracle table to SAP through SAP PI????????

Thanks for your quick help.....