尝试获取并发的最新执行（oracle 11g）

Question

我正在尝试获取特定并发的最新执行；我正在连接到 Oracle 11g 数据库。

我的查询工作正常，但由于某种原因我无法仅获得最新的执行，我的意思是 request_id

这是我的查询：

select nam.user_concurrent_program_name program,
       con.request_id "request id",
       to_char(con.actual_start_date, 'dd/mm/yyyy hh24:mi') start,
       to_char(con.actual_completion_date, 'dd/mm/yyyy hh24:mi') end,
       trunc((con.actual_completion_date - con.actual_start_date) * 1440, 2) time_mm,
       con.status_code status,
       us.user_name user,
       con.oracle_process_id,
       con.oracle_session_id,
       con.argument_text
  from fnd_concurrent_programs_tl nam,
       fnd_concurrent_requests    con,
       fnd_user                   us
 where con.concurrent_program_id = nam.concurrent_program_id
   and con.requested_by = us.user_id
   and con.actual_start_date >= to_date('20/11/2019', 'dd/mm/rrrr')
   and con.actual_start_date < to_date('23/11/2019', 'dd/mm/rrrr') + 1
   and nam.user_concurrent_program_name like 'report concurrent sales'
   and co.request_id =
       (select max(con.request_id)
          from fnd_concurrent_requests can
         where con.request_id = can.request_id);

问题是我得到了几行，我只想要最新的行，具有最高的 request_id。

你能帮帮我吗？

Answer 1

您可以使用row_number() 降序解析函数request_id（假设request_id 是作为标识的主键列，没有tie（行间重复列值) 将发生）：

select program, "request id", "start", "end", "request id", time_mm, status, "user", 
       oracle_process_id, oracle_session_id, argument_text
  from
  (
    select nam.user_concurrent_program_name program,
           con.request_id "request id",
           to_char(con.actual_start_date,'dd/mm/yyyy hh24:mi') "start",
           to_char(con.actual_completion_date,'dd/mm/yyyy hh24:mi') "end",
           trunc((con.actual_completion_date-con.actual_start_date)*1440,2) time_mm,
           con.status_code status,
           us.user_name "user",
           con.oracle_process_id,
           con.oracle_session_id,
           con.argument_text,
           row_number() over (order by con.request_id desc) as rn
      from fnd_concurrent_programs_tl nam
      join fnd_concurrent_requests con
        on con.concurrent_program_id=nam.concurrent_program_id
      join fnd_user us
        on con.requested_by = us.user_id
     where con.actual_start_date >= date'2019-11-20' 
       and con.actual_start_date <  date'2019-11-23' + 1
       and nam.user_concurrent_program_name like  'report concurrent sales'
  )  
where rn = 1 

附：注意user和end等保留关键字用引号括起来。

编辑（新案例）：您可以将子查询的where条件转换为：

 where con.actual_start_date >= date'2019-11-20' 
   and con.actual_start_date <  date'2019-11-23' + 1
   and ( nam.user_concurrent_program_name in 
                                            ('report concurrent sales',
                                             'report concurrent customers',
                                             'report concurrent sunday') )

如果您想为每个user_concurrent_program_name 分别添加一行，请添加partition by 子句

row_number() 
over (partition by nam.user_concurrent_program_name order by con.request_id desc) as rn