docs: def build_from_table(self):
          """
          Generates the sql for the FROM portion of the query
  
          :return: the FROM portion of the query
          :rtype: str
          """
          table_parts = []
  
          # get the table sql for each table
          for table in self.tables:
              sql = table.get_sql()
              if len(sql):
                  table_parts.append(sql)
  
          # combine all table sql separated by a comma
          sql = 'FROM {0} '.format(', '.join(table_parts))
  
          return sql