public int supportsUpdatableView() {
        return SyncProvider.NONUPDATABLE_VIEW_SYNC;
    }
Returns the supported updatable view abilities of the
reference implementation of the <code>SyncProvider</code>
abstract class.

@return <code>SyncProvider.NONUPDATABLE_VIEW_SYNC</code>. The
    the reference implementation does not support updating tables
    that are the source of a view.
src/main/java/org/replicadb/rowset/sun/rowset/providers/RIOptimisticProvider.java