Take a look at the samples shipped with Designer. For 8.2.1 release take a look at
C:\Program Files\Adobe\LiveCycle Designer ES\8.2\EN\Samples\Forms\Purchase Order\Schema\Schema\Purchase Order.xsd
and the form samples.
Otherwise, forward a request to firstname.lastname@example.org I would be happy to send you a sample XDP with a dynamic table and a schema.