function checkEvalRelations_NonUniqueKeys(evalFn) {
  var sampleRows = getSampleRows();

  var employeeRelation = lf.proc.Relation.fromRows(
      sampleRows.employees, [e.getName()]);
  var jobRelation = lf.proc.Relation.fromRows(
      sampleRows.jobs, [j.getName()]);

  var joinPredicate1 = e.salary.eq(j.minSalary);
  var result = evalFn.call(
      joinPredicate1, employeeRelation, jobRelation, false);
  assertEquals(
      sampleRows.employees.length * sampleRows.jobs.length,
      result.entries.length);
}
Checks that the given join implementation is correct, for the case where the
join predicate refers to non-unique keys.
@param {!function(!lf.proc.Relation, !lf.proc.Relation, boolean)
    :!lf.proc.Relation} evalFn The join implementation method should be
    either evalRelationsNestedLoopJoin_ or evalRelationsHashJoin_.