// Create keys (that exclude the temporal date/time information) from the interval
// and the data in the column discriminators.
final AggregationInterval interval = form.getInterval();
final HashSet<PortletLayoutAggregationKey> keys = new HashSet<PortletLayoutAggregationKey>();
for (PortletLayoutAggregationDiscriminator discriminator : columnDiscriminators) {
keys.add(new PortletLayoutAggregationKeyImpl(interval, discriminator.getAggregatedGroup(),
discriminator.getPortletMapping()));
}
return keys;
}