code: def get_sql(self):
          
          alias = self.get_alias()
          if alias:
              if self.cast:
                  return 'CAST({0} AS {1}) AS "{2}"'.format(self.get_select_sql(), self.cast.upper(), alias)
              return '{0} AS "{1}"'.format(self.get_select_sql(), alias)
  
          if self.cast:
              return 'CAST({0} AS {1})'.format(self.get_identifier(), self.cast.upper())
          return self.get_identifier()
docs: Gets the SELECT sql part for a field
          Ex: field_name AS alias
  
          :return: the sql for this field used in the SELECT portion of the query
          :rtype: str