13.6. Partial Results

JBoss Data Virtualization provides the capability to obtain "partial results" in the event of data source unavailability or failure. This is especially useful when unioning information from multiple sources, or when doing a left outer join, where you are 'appending' columns to a master record but still want the record if the extra information is not available.

A source is considered to be 'unavailable' if the connection factory associated with the source issues an exception in response to a query. The exception will be propagated to the query processor, where it will become a warning on the statement. See Red Hat JBoss Data Virtualization Development Guide: Client Development for more on Partial Results Mode and SQLWarnings.