2

ここでいくつかの素晴らしい答えを見てきましたが、修正が必要です。テーブルや ETL はまだ作成したくないので、ユーザーがアクセスして最初にテストできる単純なデータベース ビューを作成したいと考えていました。

テーブルには、item#、item_ticket_color#、maint_date、およびその他の列があります tick_col は時々更新されますが、テーブル内の他の列も更新されます。他の列が更新または変更された場合、 tick_col が繰り返されます。以下の期待される結果を得るには、このデータをフィルタリングする必要があり、これを行う方法を理解するために助けが必要です。可能であれば、ストレート SQL を探しています

ITEM......................TICK_COL................. MAINT_DATE

21524804....................RIBG...................1/1/0001  
21524804....................RIBG...................6/15/2008 6:52:57 AM
21524804....................RIBG...................6/25/2008 11:31:03 AM
21524804....................RIBG...................6/28/2008 4:12:21 AM
21524804....................RIWH...................9/20/2008 6:36:24 AM
21524804....................RIGR...................9/23/2008 6:36:44 AM
21524804....................RIGR...................9/30/2008 6:37:42 AM
21524804....................RIWH...................10/31/2008 6:37:27 AM
21524804....................RIWH...................11/1/2008 6:36:41 AM
21524804....................RIGR...................3/11/2009 6:01:43 PM
21524804....................RIGR...................7/28/2009 6:37:11 AM
21524804....................RIGR...................10/8/2009 6:37:00 AM
21524804....................RIBS...................11/20/2009 6:37:58 AM
21524804....................RIBS...................5/18/2010 6:37:07 AM
21524804....................RIBS...................9/16/2010 6:38:11 AM
21524804....................RIBS...................8/13/2012 10:39:44 AM
21524804....................RIBS...................3/12/2013 6:46:08 AM
21524804....................RIBS...................3/17/2013 9:25:31 AM
21524804....................RIBS...................3/27/2013 6:52:57 AM
21524804....................RIBS...................7/25/2013 6:41:51 AM

チケットの色が変更された各シナリオの開始日と終了日が示されている以下を参照してください。

21524804.....RIBG.....10101........20080919

21524804.....RIWH.....20080920.....20080922

21524804.....RIGR.....20080923.....20081030

21524804.....RIWH.....20081031.....20090310

21524804.....RIGR.....20090311.....20091119

21524804.....RIBS.....20091120.....20130725

ここで SQLFiddle。

これが Jasti の貢献に基づく新しいコードです。いくつかの追加の変更を加えましたが、これはまさに私が望んでいたものです。

 SELECT item,
       tick_col,
       from_dt,
       CASE
          WHEN LEAD (from_dt) OVER (PARTITION BY item ORDER BY from_dt) - 1
                  IS NULL
          THEN
             SYSDATE
          ELSE
             LEAD (from_dt) OVER (PARTITION BY item ORDER BY from_dt) - 1
       END
          TO_DATE
  FROM (  SELECT ITEM,
                 TICK_COL,
                 MIN (MAINT_DATE) AS from_dt,
                 MAX (MAINT_DATE) AS to_dt
            FROM (SELECT SUM (start_of_group) OVER (ORDER BY maint_date) AS sm,
                         ITEM,
                         TICK_COL,
                         maint_date
                    FROM (SELECT ITEM,
                                 TICK_COL,
                                 maint_date,
                                 CASE
                                    WHEN LAG (TICK_COL, 1, TICK_COL)
                                            OVER (ORDER BY maint_date) =
                                            TICK_COL
                                    THEN
                                       0
                                    ELSE
                                       1
                                 END
                                    start_of_group
                            FROM mytable))
        GROUP BY ITEM, TICK_COL, sm
        ORDER BY sm)
4

4 に答える 4

1

最初の部分のクエリも追加しました。次のクエリは、両方の要件を解決する必要があります。このクエリは、TICK_COL が変更されるまでアイテムをグループ化し、その特定のグループの最大日付と最小日付を計算します

select ITEM, TICK_COL, MIN(MAINT_DATE) AS from_dt, MAX(MAINT_DATE) AS to_dt from
(
  select sum(start_of_group) over (order by maint_date) as sm, ITEM, TICK_COL, maint_date from 
  (
    select  ITEM, TICK_COL,maint_date,
      case
        when 
          lag(TICK_COL,1,TICK_COL) over (order by maint_date)  = TICK_COL then 0
          else 1
         end start_of_group
    from  mytable 
  )
) group by ITEM, TICK_COL,sm order by sm

ここで SQL Fiddle を更新しました

于 2013-07-25T21:30:21.250 に答える
0

期間の開始と終了の検出に基づいてバリアントし、希望の日付を計算します。(ほぼ同じ解決策がここにあります。)

SQLフィドル

with marked_set as (
  -- mark start and end of each maintenance period
  select
    item,
    tick_col,
    maint_date,
    decode( nvl(prev_tick, tick_col||'x'), tick_col, 0, 1 ) is_start,
    decode( nvl(next_tick, tick_col||'x'), tick_col, 0, 1 ) is_end
  from (
    select
      item,
      tick_col,
      maint_date,
      lag(tick_col)  over (partition by item order by maint_date) prev_tick,
      lead(tick_col) over (partition by item order by maint_date) next_tick
    from
      mytable
  )
),
boundary_set as (
  -- Leave only start and end of each period
  -- and get dates from previous and next lines
  select
    item,
    tick_col,
    maint_date,
    is_start,
    is_end,
    ( lag(maint_date) over (
        partition by item order by maint_date)
    )                                          prev_maint_date,
    ( lead(maint_date,1,maint_date) over (
        partition by item order by maint_date
      )
    )                                          next_maint_date
  from
    marked_set
  where
    1 in (is_start, is_end)
),
maintenance_sequence as (
  -- Calculate start and end dates for each maintenance period
  select distinct
    item,
    tick_col,
    decode( is_start,
      1, maint_date,
      prev_maint_date
    )                     start_date,
    decode( is_end,
      1, next_maint_date,
      ( lead(next_maint_date,1,next_maint_date)
         over (partition by item order by maint_date)
      )
    )                    end_date
  from
    boundary_set
)
select
  -- Final formatting and ordering.
  -- For end date of last period get exact date, for others get previous date
  -- because it's date of start for maintenance of next item.
  item,
  tick_col,
  to_char(start_date, 'yyyymmdd') maint_start,
  decode( (lead(end_date) over (partition by item order by start_date)),
    null, to_char(end_date, 'yyyymmdd'),
    to_char(end_date - 1, 'yyyymmdd')
  )
   maint_end
from
  maintenance_sequence
order by
  maint_start
于 2013-07-26T06:44:01.467 に答える
0

このクエリが機能するかどうか試してみてください。

   select item,
           tick_col,
           MAINT_DATE maint_start_date,
           (case when tick_col <> next_tick_col then next_maint_date end) maint_end_date
    from (
      select item,
             tick_col,
             lead(MAINT_DATE) over (partition by item 
                                    order by MAINT_DATE asc) next_maint_date,
             lead(tick_col) over (partition by item 
                                  order by MAINT_DATE asc) next_tick_col,
      from   my_table
) where tick_col <> next_tick_col;
于 2013-07-25T20:40:02.483 に答える