Question

一直坚持找出这个问题。

商品数据库包含以下列： Customer_ID，Date，Trigger，Priority，PriorityOverRide。

我有查询选择Priority和PriorityOverride之间的最大值，但我似乎无法选择从中获取值的行。

目前我的查询是：

SELECT
Customer_ID,
CASE WHEN offers.PriorityOverride > 0 THEN offers.PriorityOverride ELSE 
Priority END AS 'Priority'
FROM
(
SELECT
    Customer_ID,
    MAX(Priority) AS Priority,
    MAX(PriorityOverride) AS PriorityOverride
FROM
    offers
GROUP BY
    CUstomer_ID
) AS offers

上述查询选择Priority和PriorityOverride的MAX值，并选择更大的值。

现在我无法选择选择优先级的日期和触发列。

编辑：更多信息： PriorityOverride可以为null或为空但如果它不为空或为null，则其值将取代优先级所具有的值。

EDIT2：这是我更新的查询：

SELECT Customer_ID, Date, Trigger_1, Priority, PriorityOverride
  FROM Offers
  WHERE (Customer_ID, Priority) in (
    SELECT
        Customer_ID,
        CASE WHEN
            MAX(PriorityOverride) > 0
        THEN
            MAX(PriorityOverride)
        ELSE
            MAX(Priority)
        END AS 'Priority'
    FROM
        Offers
    GROUP BY
        Customer_ID
  ) 
  OR (Customer_ID, PriorityOverride) in (
    SELECT
        Customer_ID,
        CASE WHEN
            MAX(PriorityOverride) > 0
        THEN
            MAX(PriorityOverride)
        ELSE
            MAX(Priority)
        END AS 'Priority'
    FROM
        Offers
    GROUP BY
        Customer_ID
  )

但是上面的查询给了我一个错误＆＃34;错误：在预期条件的上下文中指定的非布尔类型的表达式，在＆＃39;附近，＆＃39;。＆＃39;

Answer 1

您可以使用“最大”来获取max valeus和过滤器之间的较大位，以便在Customer_ID，Priority或Customer_ID，PriorityOverride上匹配值

  select Customer_ID, Date, Trigger, Priority, PriorityOverRide
  from offers 
  where (Customer_ID, Priority) in (
    SELECT
        Customer_ID,
        max( case when Priority >  PriorityOverride
          THEN Priority
          ELSE  PriorityOverride
        end )
    FROM  offers
    GROUP BY  CUstomer_ID
  ) 
  or  (Customer_ID, PriorityOverride) in (
    SELECT
        Customer_ID,
        max(case when Priority >  PriorityOverride
          THEN Priority
          ELSE  PriorityOverride
        end )
    FROM  offers
    GROUP BY  CUstomer_ID
  )

选择两个表之间具有最高值的行，同时还按

1 个答案: