Question

WITH A   -- Get a list of unique combinations of Shipmentnumber and ShipmentType
AS  (
   SELECT Distinct
          f_Shipmentnumber
     ,    f_ShipmentType
   FROM  t_shipment
)
,   B  -- Get a list of all those shipmentnumbers values that have more than one shipmentType associated
AS  (
    SELECT f_Shipmentnumber
    FROM   A
    GROUP BY
           f_Shipmentnumber
    HAVING COUNT(*) > 1
)
SELECT 
         A.f_Shipmentnumber
    ,    A.f_ShipmentType
FROM    A
    JOIN B
        ON  A.f_Shipmentnumber = B.f_Shipmentnumber

这就是我所拥有的并且它返回的很漂亮然而我需要设置shipmentType = 1，其中shipmentTyp = 2只是为了这些结果。

Answer 1

您可以使用另一个CTE进行最后一次选择，然后只使用更新语句：

WITH A   -- Get a list of unique combinations of Shipmentnumber and ShipmentType
AS  (
   SELECT Distinct
          f_Shipmentnumber
     ,    f_ShipmentType
   FROM  t_shipment
)
,   B  -- Get a list of all those shipmentnumbers values that have more than one shipmentType associated
AS  (
    SELECT f_Shipmentnumber
    FROM   A
    GROUP BY
           f_Shipmentnumber
    HAVING COUNT(*) > 1
), C -- This CTE will be the one for your update statement, assuming that f_shipmentnumber is a primary key
AS ( 
    SELECT 
             A.f_Shipmentnumber
        ,    A.f_ShipmentType
    FROM    A
        JOIN B
            ON  A.f_Shipmentnumber = B.f_Shipmentnumber
)
UPDATE t_shipment
SET f_ShipmentType = 1
FROM C as cte
   JOIN t_shipment s ON cte.f_shipmentnumber = s.f_shipmentnumber
WHERE cte.f_shipmenttype = 2

请注意，update语句只是通过f_shipmentnumber加入最终的CTE结果，更新只会更新最终select语句中返回的记录，现在包含在CTE中。

Answer 2

如果您想要1更改2，请使用CASE

SELECT 
         CASE WHEN A.f_Shipmentnumber = 2
              THEN 1
              ELSE A.f_Shipmentnumber
         END as f_Shipmentnumber
    ,    A.f_ShipmentType
FROM    A
    JOIN B
        ON  A.f_Shipmentnumber = B.f_Shipmentnumber

如何对查询结果运行sql更新

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