Question

表：哪个角色实例更改了时间

Sr No | TIMESTAMP                         |  RoleInstance   | Id  
1     | 2012-03-14 12:00:00.000           | SLBMRole_IN_1   | 120007  
2     | 2012-03-14 12:01:00.000           | SLBMRole_IN_1   | 120007  
3     | 2012-03-14 12:02:00.000           | SLBMRole_IN_1   | 120007  
4     | 2012-03-14 12:24:00.000           | SLBMRole_IN_0   | 120007  
5     | 2012-03-14 12:25:00.000           | SLBMRole_IN_0   | 120007  
5     | 2012-03-14 12:26:00.000           | SLBMRole_IN_0   | 120007  
6     | 2012-03-14 12:27:00.000           | SLBMRole_IN_1   | 120007  
7     | 2012-03-14 12:28:00.000           | SLBMRole_IN_1   | 120007

下面基于上表的新表，以便在RoleInstance中更改时获取值

RoleInstance  | Start time                |  End Time  
SLBMRole_IN_1 |     1st row Time stamp    |  3rd row time stamp(bcz 4th row RoleInstance changed)   
SLBMRole_IN_0 |     4th row time stamp    |   5th row time stamp  
SLBMRole_IN_1 |     6th row time stamp    |   …so on and so forth

所以基本上当RoleInstance改变时，我需要得到相同的开始时间和结束时间我可以获得一个查询来实现上面的输出表吗？

Answer 1

select *,rn = row_number() over (order by timestamp,roleinstance)
into    #temp2
from #temp1

我发现srno正在重复，因此我先添加了行号

select  a.*
from    #temp2 a
where   rn = 1
union all
select  a.*
from    #temp2 a, #temp2 b
where   a.rn+1 = b.rn
and     a.roleinstance <> b.roleinstance
union all
select  a.*
from    #temp2 a, #temp2 b
where   a.rn = b.rn +1
and     a.roleinstance <> b.roleinstance
order by a.rn

添加行号后，此查询将提供所需的结果

Answer 2

我在这里假设SrNo是顺序的。我这样说是因为SrNo 5已被复制。以下查询将解决这个问题：

CREATE TABLE #temp (SrNo INT,  DTS DATETIME, RoleInstance VARCHAR(30), Id INT)
INSERT INTO #temp VALUES
    (1,'2012-03-14 12:00:00.000','SLBMRole_IN_1',120007),
    (2,'2012-03-14 12:01:00.000','SLBMRole_IN_1',120007), 
    (3,'2012-03-14 12:02:00.000','SLBMRole_IN_1',120007),
    (4,'2012-03-14 12:24:00.000','SLBMRole_IN_0',120007),
    (5,'2012-03-14 12:25:00.000','SLBMRole_IN_0',120007),
    (6,'2012-03-14 12:26:00.000','SLBMRole_IN_0',120007),
    (7,'2012-03-14 12:27:00.000','SLBMRole_IN_1',120007),
    (8,'2012-03-14 12:28:00.000','SLBMRole_IN_1',120007)

WITH Logins AS (
    SELECT t2.SrNo, ROW_NUMBER() OVER (ORDER BY t2.SrNo) AS join_no, t2.RoleInstance, t2.DTS, t2.Id
    FROM #temp t2 LEFT JOIN #temp t1 ON t2.SrNo = t1.SrNo +1
    WHERE t1.RoleInstance <> t2.RoleInstance OR t1.RoleInstance IS NULL),
Logouts AS (
    SELECT t1.SrNo, ROW_NUMBER() OVER (ORDER BY t1.SrNo) AS join_no, t1.RoleInstance, t1.DTS, t1.Id
    FROM #temp t1 LEFT JOIN #temp t2 ON t2.SrNo = t1.SrNo +1
    WHERE t1.RoleInstance <> t2.RoleInstance OR t2.RoleInstance IS NULL)
SELECT i.Id, i.RoleInstance, i.SrNo AS InSrNo, i.DTS AS InDTS, o.SrNo AS OutSrNo, o.DTS AS OutDTS
FROM Logins i INNER JOIN Logouts o ON i.join_no = o.join_no

两个公用表表达式（Logins和Logouts）分别检索给定RoleInstance的更改和给定RoleInstance的更改。第一个执行从第二个到第一个后续记录的左连接，允许两个中的第一个为空以检索第一个登录。第二个反过来，检索最后一次注销。然后将它们连接到由ROW_NUMBER（）函数生成的密钥。

SQL查询根据以下条件从两个表中检索数据

2 个答案: