function getRelation() {
  var relation = lf.proc.Relation.fromRows(sampleJobs, [j.getName()]);

  // Filling in dummy aggregation results. In a normal scenario those have been
  // calculated before ProjectStep executes.
  relation.setAggregationResult(lf.fn.avg(j.maxSalary), 50);
  relation.setAggregationResult(lf.fn.max(j.maxSalary), 100);
  relation.setAggregationResult(lf.fn.min(j.maxSalary), 0);

  var entry1 = new lf.proc.RelationEntry(
      new lf.Row(1, {'maxSalary': 1000}), false);
  var entry2 = new lf.proc.RelationEntry(
      new lf.Row(1, {'maxSalary': 2000}), false);
  var distinctRelation = new lf.proc.Relation([entry1, entry2], [j.getName()]);
  relation.setAggregationResult(lf.fn.distinct(j.maxSalary), distinctRelation);
  return relation;
}
Generates a dummy relation, with bogus aggregation results to be used for
tesing.
@return {!lf.proc.Relation}