Getting wrong next date from a date column for all customer Oracle

问题

This is my NM_CUST_APPLIANCE_HISTORY table ( for custoner_id=96 ) .

Customer_id   | Last_effective_date | Present_quentity
--------------+---------------------+-----------------
    96        | 2009-12-20          | 10
    96        | 2014-11-18          | 12
    96        | 2015-11-26          | 14

I execute my query to get start_date and immediate date of next row as a end_date for a single customer ( customer_id=96 ) .

  SELECT NM.CUSTOMER_ID customer_id,
     NM.LATEST_EFFECTIVE_DATE start_date,
     NVL (
        CASE
           WHEN nm.LATEST_EFFECTIVE_DATE IS NULL
           THEN
              TO_DATE ('12/12/9999', 'dd/mm/yyyy')
           ELSE
              FIRST_VALUE (
                 nm.LATEST_EFFECTIVE_DATE)
              OVER (ORDER BY nm.LATEST_EFFECTIVE_DATE
                    RANGE BETWEEN 1 FOLLOWING AND UNBOUNDED FOLLOWING)
        END,
        TO_DATE ('12/12/9999', 'dd/mm/yyyy'))
        end_date,
     NM.PRESENT_QUANTITY PRESENT_quantity
FROM nm_cust_appliance_history nm
WHERE NM.APPLIANCE_INFO_ID = 10484 
AND NM.CUSTOMER_ID = 96
ORDER BY customer_id, start_date;

And the result comes perfectly AS I WANT. like below :

Customer_id | START_DATE |  END_DATE  | PRESENT_QUANTITY
------------+------------+------------+-----------------
    96      | 2009-12-20 | 2014-11-18 |      10
    96      | 2014-11-18 | 2015-11-26 |      12
    96      | 2015-11-26 | 9999-12-12 |      14

But when i execute this query for all customer ( removing NM.CUSTOMER_ID = 96 from query ) it gives me same START_DATE and END_DATE and end_date comes added a day AS LIKE below ... I i also give you a snapshot of my output of query and marked out that customer result with red color box...

  SELECT NM.CUSTOMER_ID customer_id,
     NM.LATEST_EFFECTIVE_DATE start_date,
     NVL (
        CASE
           WHEN nm.LATEST_EFFECTIVE_DATE IS NULL
           THEN
              TO_DATE ('12/12/9999', 'dd/mm/yyyy')
           ELSE
              FIRST_VALUE (
                 nm.LATEST_EFFECTIVE_DATE)
              OVER (ORDER BY nm.LATEST_EFFECTIVE_DATE
                    RANGE BETWEEN 1 FOLLOWING AND UNBOUNDED FOLLOWING)
        END,
        TO_DATE ('12/12/9999', 'dd/mm/yyyy'))
        end_date,
     NM.PRESENT_QUANTITY PRESENT_quantity
FROM nm_cust_appliance_history nm
WHERE NM.APPLIANCE_INFO_ID = 10484
--AND NM.CUSTOMER_ID = 96
ORDER BY customer_id, start_date;

Result is:

Customer_id   | START_DATE  |  END_DATE  | Present_quentity
--------------+-------------+------------+-----------------
    74        | 2008-10-26  | 2008-10-27 |  5
 >  96        | 2009-12-20  | 2009-12-21 | 10
 >  96        | 2014-11-18  | 2014-11-19 | 12
 >  96        | 2015-11-26  | 2015-11-27 | 14
   100        | 2009-01-07  | 2009-01-09 |  7

Image of query Result

I want the result for all customer like the result of single customer. How can i solve my problem? Help me any one

回答1:

Your window clause is looking at last_effective_dates across all your data. You need to add a partition by clause to restrict it to the current customer:

  OVER (PARTITION BY nm.CUSTOMER_ID
        ORDER BY nm.LATEST_EFFECTIVE_DATE
        RANGE BETWEEN 1 FOLLOWING AND UNBOUNDED FOLLOWING)

So:

  SELECT NM.CUSTOMER_ID customer_id,
     NM.LATEST_EFFECTIVE_DATE start_date,
     NVL (
        CASE
           WHEN nm.LATEST_EFFECTIVE_DATE IS NULL
           THEN
              TO_DATE ('12/12/9999', 'dd/mm/yyyy')
           ELSE
              FIRST_VALUE (
                 nm.LATEST_EFFECTIVE_DATE)
              OVER (PARTITION BY nm.CUSTOMER_ID
                    ORDER BY nm.LATEST_EFFECTIVE_DATE
                    RANGE BETWEEN 1 FOLLOWING AND UNBOUNDED FOLLOWING)
        END,
        TO_DATE ('12/12/9999', 'dd/mm/yyyy'))
        end_date,
     NM.PRESENT_QUANTITY PRESENT_quantity
FROM nm_cust_appliance_history nm
WHERE NM.APPLIANCE_INFO_ID = 10484
ORDER BY customer_id, start_date;

If you ever need to run it for more than one appliance_info_id then you'll need to add that to the partition by clause too.

Using a dummy extra record to kind of simulate what you're seeing, supplied via a CTE:

with nm_cust_appliance_history(appliance_info_id, customer_id, latest_effective_date, present_quantity) as (
  select 10484, 96, date '2009-12-20', 10 from dual
  union all select 10484, 96, date '2014-11-18', 12 from dual
  union all select 10484, 96, date '2015-11-26', 14 from dual
  union all select 10484, 42, date '2009-12-21', 15 from dual
)

your original query gets:

CUSTOMER_ID START_DATE END_DATE   PRESENT_QUANTITY
----------- ---------- ---------- ----------------
         42 2009-12-21 2014-11-18               15
         96 2009-12-20 2009-12-21               10
         96 2014-11-18 2015-11-26               12
         96 2015-11-26 9999-12-12               14

and the partition-by query above gets:

CUSTOMER_ID START_DATE END_DATE   PRESENT_QUANTITY
----------- ---------- ---------- ----------------
         42 2009-12-21 9999-12-12               15
         96 2009-12-20 2014-11-18               10
         96 2014-11-18 2015-11-26               12
         96 2015-11-26 9999-12-12               14

来源：https://stackoverflow.com/questions/46826305/getting-wrong-next-date-from-a-date-column-for-all-customer-oracle