Question

我有2个表，Jobs和AdminUsersLog。 AdminUsersLog包含对Jobs中每个作业记录执行的操作的日志。

我正在尝试检索已闲置超过7天的作业列表。下面的SQL似乎是为每个作业提取所有日志条目，因此从日志中提取旧条目，当然这些条目总是超过7天。

我需要为AdminUsersLog.ulDate超过7天的每个作业检索一条记录。

SELECT DISTINCT Jobs.ID, Jobs.bStatus AS jStatus,  Jobs.sID, Jobs.insDate, Jobs.statusLabel, Jobs.cID, AdminUsersLog.ulDate, AdminUsersLog.ulJobType
FROM AdminUsersLog LEFT JOIN Jobs
ON (AdminUsersLog.ulJobID = Jobs.ID AND AdminUsersLog.ulJobType = 1) 
WHERE AdminUsersLog.ulJobType = 1 
AND (SELECT TOP(1) AdminUsersLog.ulDate FROM AdminUsersLog WHERE AdminUsersLog.ulJobID =     Jobs.ID AND AdminUsersLog.ulJobType = 1) < DATEADD(dd,-7,GETDATE()) 
AND Jobs.bStatus < 8

前X名结果; http://pastebin.com/RcvxbxCV

Answer 1

您设置了您的upDate列

AS

  SELECT CONVERT(DATE,ulDate) AS ulDate

选择字段

 SELECT CAST('2014-01-23 15:23:42.093' AS DATE) like this

因为你的upDate字段并不明显

查询SET AS

    SELECT      DISTINCT Jobs.ID, Jobs.bStatus AS jStatus,  Jobs.sID, Jobs.insDate, Jobs.statusLabel, Jobs.cID, 
                CONVERT(DATE,AdminUsersLog.ulDate) AS ulDate, AdminUsersLog.ulJobType
    FROM        AdminUsersLog 
    LEFT JOIN   Jobs ON (AdminUsersLog.ulJobID = Jobs.ID AND AdminUsersLog.ulJobType = 1) 
    WHERE       AdminUsersLog.ulJobType = 1 
                AND (SELECT TOP(1) AdminUsersLog.ulDate FROM AdminUsersLog WHERE AdminUsersLog.ulJobID = Jobs.ID AND AdminUsersLog.ulJobType = 1) < DATEADD(dd,-7,GETDATE()) 
                AND Jobs.bStatus < 8

Answer 2

看看

SELECT TOP(1) AdminUsersLog.ulDate 
FROM AdminUsersLog 
WHERE AdminUsersLog.ulJobID = Jobs.ID AND AdminUsersLog.ulJobType = 1

这将为您提供工作条目。这可以是任何匹配的条目，因为您没有为TOP表达式指定排序顺序。通常随机挑选的条目将是旧的。因此要么指定排序顺序：

SELECT TOP(1) AdminUsersLog.ulDate 
FROM AdminUsersLog 
WHERE AdminUsersLog.ulJobID = Jobs.ID AND AdminUsersLog.ulJobType = 1
ORDER BY ulDate DESC

或者只是使用MAX：

SELECT MAX(AdminUsersLog.ulDate)
FROM AdminUsersLog 
WHERE AdminUsersLog.ulJobID = Jobs.ID AND AdminUsersLog.ulJobType = 1

为什么此SQL语句不检索DISTINCT记录

2 个答案: