public CollectNode normalize(EvaluatingNormalizer normalizer) {
assert whereClause() != null;
CollectNode result = this;
List<Symbol> newToCollect = normalizer.normalize(toCollect());
boolean changed = newToCollect != toCollect();
WhereClause newWhereClause = whereClause().normalize(normalizer);
if (newWhereClause != whereClause()) {
changed = changed || newWhereClause != whereClause();
}
if (changed) {
result = new CollectNode(id(), routing, newToCollect, projections);