Oracle 我们如何将多行转换成单行

我的预期产出是：

ACCOUNT_NUM    IMSI           PREVIOUS_MONTH         CURRENT_MONTH
ACC000142   310640100000003  10/8/2015 5:18:29 AM   
ACC000142   310640100000003                        11/3/2015 11:25:33 PM
ACC000142   310640100000003                         11/3/2015 5:18:29 AM
ACC000142   310640100000003  10/8/2015 11:25:33 PM  

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看起来你想做的是

ACCOUNT_NUM    IMSI           PREVIOUS_MONTH             CURRENT_MONTH
ACC000142   310640100000003  10/8/2015 5:18:29 AM   11/3/2015 11:25:33 PM

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祝你好运。

看来你想做的事情

ACCOUNT_NUM    IMSI           PREVIOUS_MONTH             CURRENT_MONTH
ACC000142   310640100000003  10/8/2015 5:18:29 AM   11/3/2015 11:25:33 PM

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祝你好运。

有人能帮我吗……有人能帮我吗。。。

with ces as (select account_num,
                    imsi,
                    u.previous_month,
                    u.current_month
                    ls.status  
               from (select account_num,
                            imsi,
                            case
                              when usage_date < add_months(to_date('20151110','yyyymmdd'),-1) then usage_date
                              else null
                            end previous_month,
                            case
                              when usage_date >= add_months(to_date('20151110','yyyymmdd'),-1) then usage_date
                              else null
                            end current_month
                       from genevabatchuser.loadusagedata
                       where event_source = 'NUMEREXROMHYB' and
                             account_num = 'ACC000142' and
                             imsi in ('310640100000003','310640100000004','310640100000338','310640100000331'))u
               full outer join GENEVABATCHUSER.TMOLOADIMSILIST ls  
                 using (account_num, imsi))
select ACCOUNT_NUM,
       IMSI,
       MIN(PREVIOUS_MONTH) AS PREVIOUS_MONTH,
       MAX(CURRENT_MONTH) AS CURRENT_MONTH
  from ces 
  where imsi in ('310640100000003','310640100000004','310640100000338','310640100000331')
  GROUP BY ACCOUNT_NUM, IMSI;