Question

这是我当前查询所产生的：

EventID Sku         User1           LogTime
3510    02821-99-0  Item Inducted   2019-07-08
3510    02821-99-0  Item Inducted   2019-07-06
3510    12573-88-L  Item Inducted   2019-07-08
3510    12573-88-L  Item Inducted   2019-07-07
3510    12948-96-M  Item Inducted   2019-07-06
3510    12948-96-M  Item Inducted   2019-07-05
3510    12948-96-M  Item Inducted   2019-07-05

我想要的是：（每个SKU的最新事件ID 3510）

EventID Sku         User1           LogTime
3510    02821-99-0  Item Inducted   2019-07-08
3510    12573-88-L  Item Inducted   2019-07-08
3510    12948-96-M  Item Inducted   2019-07-06

我尝试使用MAX FUNCTION，但查询失败。

以下是我当前正在使用的查询：

select
tl.EventID,
tl.Sku,
tl.User1,
--MAX(tl.LogTime) as 'LogTime'
tl.LogTime

from dmhost.tblTransactionLog tl

where tl.logTime between '7/5/2019' and '7/9/2019'
and tl.sku not like 'NULL'
and tl.sku <> ''
and tl.sku not like 'Unknown'
and tl.EventID like '3510'

--group by tl.Sku,tl.EventID
order by tl.Sku

我评论了我尝试过的内容。谢谢！

Answer 1

这将在SQL Server和MySQL中工作。（https://www.db-fiddle.com/f/kDhqfwDG2bUcqm5GKUbdj3/0）

首先为EventID和Sku的每种组合获取最大LogTime，然后从tblTransactionLog加入该日志。

SELECT     tl.EventID
         , tl.Sku
         , tl.User1
         , tl.LogTime
FROM       dmhost.tblTransactionLog tl
INNER JOIN (
               SELECT EventID
                    , Sku
                    , MAX(LogTime) AS MaxLogTime
               FROM   dmhost.tblTransactionLog
               WHERE  LogTime BETWEEN '7/5/2019' AND '7/9/2019'
           GROUP BY   EventID, Sku
           ) AS tmax ON tl.EventID = tmax.EventID
                        AND tl.Sku = tmax.Sku
                        AND tl.LogTime = tmax.MaxLogTime
WHERE    tl.LogTime BETWEEN '7/5/2019' AND '7/9/2019'

Answer 2

对于按row_number()和EventID列进行分区，以及由于Sku采用最新的LogTime分区，您可以使用窗口分析功能order by LogTime desc：< / p>

select q.EventID, q.Sku, q.User1, q.LogTime
  from
  (
   select tl.EventID, tl.Sku, tl.User1, t1.LogTime
          row_number() over (partition by tl.EventID, t1.Sku order by tl.LogTime desc) as rn
     from dmhost.tblTransactionLog tl    
    where tl.logTime between '2019-07-05' and '2019-07-09'
      and tl.sku not like 'NULL'
      and tl.sku <> ''
      and tl.sku not like 'Unknown'
      and tl.EventID like '3510'
  ) q
where rn = 1
order by q.Sku

Answer 3

我建议将此查询写为：

select tl.EventID, tl.Sku, tl.User1, tl.LogTime
from (select tl.*,
             row_number() over (partition by tl.EventID, tl.sku order by tl.logTime desc) as seqnum
      from dmhost.tblTransactionLog tl
      where tl.logTime >= '2019-07-05' and
            tl.logtime < '2019-07-09' and
            tl.sku not in ('NULL', '', 'Unknown') and
            tl.EventID like 3510
     ) tl
where seqnum = 1
order by tl.Sku;

注意：

使用正确的日期/时间格式，以便它们无歧义。我更喜欢连字符（ISO 8601标准）。 SQL Server首选不带连字符的值。
您的comparisons on sku is simplified using字符串不可用。
EventID看起来像一个数字，所以我假设它是数字，并删除了引号进行比较，并将LIKE更改为=。
亚伦·伯特兰德（Aaron Bertrand）很好explanation为何不希望将BETWEEN与日期/时间值一起使用。

如何为每个SKU返回最新的LogTime

3 个答案: