SQL查询-分区依据

Question

From below table, need to fetch all records in green. For each group partitioned by sfdc_acc column, retrieve the latest record on the basis of status. In case if status is Available or NotAvailable in one partition, need to retrieve the latest record with Available.

This query is not returning the proper result as expected:

SELECT 
    A.* 
FROM
    (SELECT 
         TEMP.*,
         ROW_NUMBER () OVER (PARTITION BY ERP_ACC 
                             ORDER BY LASTMODIFIEDDATE DESC, STATUS ASC) AS RN 
     FROM 
         TEMP) A 
WHERE 
    A.RN = 1

How should I modify the query to include status check in partition clause?

Answer 1

Why don't you apply filter for Available records only.

SELECT A.* FROM
(
    SELECT TEMP.*,ROW_NUMBER () OVER (PARTITION BY ERP_ACC ORDER BY LASTMODIFIEDDATE DESC) AS RN FROM TEMP
    where STATUS = 'Available'
) A WHERE A.RN=1

Answer 2

I think you want:

SELECT A.*
FROM (SELECT T.*,
             ROW_NUMBER () OVER (PARTITION BY ERP_ACC, STATUS ORDER BY LASTMODIFIEDDATE DESC) AS RN
      FROM TEMP T
     ) T
WHERE STATUS = 'Available' AND T.RN = 1;

Answer 3

assuming that you only need the available status:

DECLARE @Table TABLE ( LASTMODIFIEDDATE DATETIME, ERP_ACC int, sfdc_acc VARCHAR(20), status VARCHAR(20))

INSERT INTO @Table VALUES ('3/31/2017', 156, 'ABC', 'Available')
INSERT INTO @Table VALUES ('3/30/2017', 678, 'ABC', 'Available')
INSERT INTO @Table VALUES ('10/17/2016', 872, 'ABC', 'Available')
INSERT INTO @Table VALUES ('08/02/2016', 900, 'ABC', 'Available')
INSERT INTO @Table VALUES ('06/09/2017', 100, 'GHK', 'Not Available')
INSERT INTO @Table VALUES ('05/01/2017', 456, 'GHK', 'Not Available')
INSERT INTO @Table VALUES ('08/02/2016', 954, 'GHK', 'Available')

Updated my answer, notice the condition to set to rank Status. if Available then 1, if not, then 2. this would ensure that all records with status "Available" is the priority.

SELECT * FROM 
(SELECT LASTMODIFIEDDATE,
        ERP_ACC,
        sfdc_acc,
        status, ROW_NUMBER () OVER (PARTITION BY sfdc_acc 
        ORDER BY 
        CASE WHEN status = 'Available' THEN 1 ELSE 2 END ASC, 
        LASTMODIFIEDDATE DESC) AS RN FROM @Table) A
WHERE A.RN = 1 

Answer 4

Something like this should work. You need to sort by status first then by timestamp to put 'Available' records first then everything else second.

SELECT 
    A.* 
FROM
    (SELECT 
         TEMP.*,
         ROW_NUMBER () OVER (PARTITION BY ERP_ACC 
                             ORDER BY CASE WHEN STATUS = 'Available' THEN 1 ELSE 2 END, LASTMODIFIEDDATE DESC) AS RN 
     FROM 
         TEMP) A 
WHERE 
    A.RN = 1