@Override
protected RelationPlan visitSampledRelation(SampledRelation node, Void context) {
if (node.getColumnsToStratifyOn().isPresent()) {
throw new UnsupportedOperationException("STRATIFY ON is not yet implemented");
}
RelationPlan subPlan = process(node.getRelation(), context);
TupleDescriptor outputDescriptor = analysis.getOutputDescriptor(node);
double ratio = analysis.getSampleRatio(node);
Symbol sampleWeightSymbol = null;
if (node.getType() == SampledRelation.Type.POISSONIZED) {
sampleWeightSymbol = symbolAllocator.newSymbol("$sampleWeight", BIGINT);
}
PlanNode planNode =
new SampleNode(
idAllocator.getNextId(),
subPlan.getRoot(),
ratio,
SampleNode.Type.fromType(node.getType()),
node.isRescaled(),
Optional.ofNullable(sampleWeightSymbol));
return new RelationPlan(
planNode,
outputDescriptor,
subPlan.getOutputSymbols(),
Optional.ofNullable(sampleWeightSymbol));
}
