hive sql error: ParseException in subquery source
org.apache.hadoop.hive.ql.parse.ParseException:line 368:18 cannot recognize input near ‘group’ ‘by’ ‘order_phone_num’ in subquery source
sql：

     customer_Flag as (

                  select order_phone_num,
                         concat_ws(';', collect_list(c)) as a,
                         sum(customer_flag)              as b
                  from (
                           select order_phone_num,
                                  customer_flag,
                                  concat_ws(',', collect_list(cast(r_diff as string))) as c
                            from add_payment_period
                           group by order_phone_num,
                                    customer_flag
                       )
                  group by order_phone_num

     ),

Solution: give the outermost group by order_phone_Num plus an alias C1

     customer_Flag as (

                  select order_phone_num,
                         concat_ws(';', collect_list(c)) as a,
                         sum(customer_flag)              as b
                  from (
                           select order_phone_num,
                                  customer_flag,
                                  concat_ws(',', collect_list(cast(r_diff as string))) as c
                            from add_payment_period
                           group by order_phone_num,
                                    customer_flag
                       ) c1
                  group by order_phone_num

     ),