docs: private SqlNode getAgg(SqlSelect select) {
  		final SelectScope selectScope = getRawSelectScope(select);
  		if (selectScope != null) {
  			final List<SqlNode> selectList = selectScope.getExpandedSelectList();
  			if (selectList != null) {
  				return aggFinder.findAgg(selectList);
  			}
  		}
  		return aggFinder.findAgg(select.getSelectList());
  	}