function checkTransformationWithoutJoin(columns, expectedResultCount) {
  var transformer = new lf.proc.RelationTransformer(getRelation(), columns);
  var transformedRelation = transformer.getTransformed();

  assertEquals(expectedResultCount, transformedRelation.entries.length);
  assertColumnsPopulated(columns, transformedRelation);

  return transformedRelation;
}
Checks that performing a transformation on a relationship that is *not* the
result of a natural join, results in a relation with fields that are
populated as expected.
@param {!Array<!lf.schema.Column>} columns The columns to be requested.
@param {number} expectedResultCount The expected number of results.
@return {!lf.proc.Relation} The transformed relation.