我用两个kaka表做temporal join时报这个错误怎么办？

org.apache.flink.table.api.TableException: Processing-time temporal join is not supported yet.

sql如下，我看官网上好像支持这种呢，不知道什么情况

create view visioned_table as  

  select

   user_id,

   event

 from

(select

    user_id,

    event,

    row_number() over(partition by user_id order by event_time desc) as rn

    from kafka_table1

    )ta where rn=1;

select

      t1.,t2.

    from mvp_rtdwd_event_app_quit t1

 join visioned_table FOR SYSTEM_TIME AS OF t1.proc_time AS t2

   on t1.user_id=t2.user_id 

   where t1.user_id is not null*来自志愿者整理的flink邮件归档