}
// sanity check the solution set delta and cancel out the delta node, if it is not needed
for (Iterator<PlanNode> deltaPlans = solutionSetDeltaCandidates.iterator(); deltaPlans.hasNext(); ) {
SingleInputPlanNode candidate = (SingleInputPlanNode) deltaPlans.next();
GlobalProperties gp = candidate.getGlobalProperties();
if (gp.getPartitioning() != PartitioningProperty.HASH_PARTITIONED || gp.getPartitioningFields() == null ||
!gp.getPartitioningFields().equals(this.solutionSetKeyFields))
{
throw new CompilerException("Bug: The solution set delta is not partitioned.");
}
}
// 5) Create a candidate for the Iteration Node for every remaining plan of the step function.
final GlobalProperties gp = new GlobalProperties();
gp.setHashPartitioned(this.solutionSetKeyFields);
gp.addUniqueFieldCombination(this.solutionSetKeyFields);
final LocalProperties lp = new LocalProperties();
lp.addUniqueFields(this.solutionSetKeyFields);
// take all combinations of solution set delta and workset plans