获取不同的行以在SQL Server中重叠时间戳 [英] Getting distinct rows for overlapping timestamp in SQL Server
问题描述
我有以下从SQL Server获得的结果集:
employeeNumber | start_date | start_time | end_date | end_time
---------------+------------+------------+--------------+----------
123 | 10-03-2020 | 18:13:55 | 10-03-2020 | 22:59:46
123 | 10-03-2020 | 18:24:22 | 10-03-2020 | 22:59:51
123 | 10-03-2020 | 23:24:22 | 10-03-2020 | 23:59:51
123 | 11-03-2020 | 18:25:25 | 11-03-2020 | 20:59:51
123 | 12-03-2020 | 18:40:22 | 12-03-2020 | 22:59:52
在某些情况下,我有多行具有与上述相同的重叠时间(行1和2),但开始和结束时间不同(以秒或分钟为单位的差异).
虽然我的查询是一个简单的选择查询,可从源表中获取数据,但我可以在where子句中添加什么以获取此类重叠时间戳行的不同行.也就是说,对于上述查询,我希望结果集返回以下内容:
employeeNumber | start_date | start_time | end_date | end_time
---------------+------------+------------+--------------+----------
123 | 10-03-2020 | 18:13:55 | 10-03-2020 | 22:59:46
123 | 10-03-2020 | 23:24:22 | 10-03-2020 | 23:59:51
123 | 11-03-2020 | 18:25:25 | 11-03-2020 | 20:59:51
123 | 12-03-2020 | 18:40:22 | 12-03-2020 | 22:59:52
以下是我的查询:
select
employeeNumber, start_date, start_time, end_date, end_time
from
emp_data
where
employeeNumber = 123
order by
employeeNumber;
我可能只提取第一条记录,但是where子句将是什么.
感谢您的帮助,因为我对SQL Server不太熟悉.
这很复杂.您需要跟踪开始"和结束".我将假设您的列是datetime
或可以合并到单个列中的类似内容:
with e as (
select e.employeeNumber, v.dt, sum(v.inc) as inc,
sum(sum(v.inc)) over (partition by e.employeeNumber order by v.dt) as in_outs
from emp_data e cross apply
(values (start_date + start_time, 1),
(end_date + end_time, -1)
) v(dt, inc)
group by e.employeeNumber, v.dt
)
select employeeNumber, min(dt) as start_datetime, max(dt) as end_datetime
from (select e.*,
sum(case when in_outs = 0 then 1 else 0 end) over (partition by employeeNumber order by dt) as grp
from e
) e
where in_outs <> 0
group by employeeNumber, grp;
此处是db< fiddle.
这是做什么的?
- 首先将日期/时间转换为日期时间.
- 然后将这些列取消显示,并分别标识为开始和结束以及+1或-1,以指示员工当时在进入"还是现有".
- 这些是累积的.
- 现在您有一个缺口和孤岛的问题,您想在其中查找"in"的连续期间. 岛屿"是使用"ins"的累积总和来标识的.
- 然后将这些汇总.
您可以将累计金额替换为:
from (select e.*,
(select sum(case when e2.in_outs = 0 then 1 else 0 end)
from e e2
where e2.employeeNumber = e.employeeNumber
e2.dt <= e.dt
) as grp
from e
) e
I have the following result set which I get from SQL Server:
employeeNumber | start_date | start_time | end_date | end_time
---------------+------------+------------+--------------+----------
123 | 10-03-2020 | 18:13:55 | 10-03-2020 | 22:59:46
123 | 10-03-2020 | 18:24:22 | 10-03-2020 | 22:59:51
123 | 10-03-2020 | 23:24:22 | 10-03-2020 | 23:59:51
123 | 11-03-2020 | 18:25:25 | 11-03-2020 | 20:59:51
123 | 12-03-2020 | 18:40:22 | 12-03-2020 | 22:59:52
For some cases I have multiple rows for the same overlapping time (row 1 and 2) as above but with a different start and end time (difference in seconds or minutes).
While my query is a simple select query that fetches the data from the source table, What can i add in the where clause to fetch distinct rows for such overlapping timestamp rows. i.e. for the above query i would want the result set to return the following :
employeeNumber | start_date | start_time | end_date | end_time
---------------+------------+------------+--------------+----------
123 | 10-03-2020 | 18:13:55 | 10-03-2020 | 22:59:46
123 | 10-03-2020 | 23:24:22 | 10-03-2020 | 23:59:51
123 | 11-03-2020 | 18:25:25 | 11-03-2020 | 20:59:51
123 | 12-03-2020 | 18:40:22 | 12-03-2020 | 22:59:52
Below is my query :
select
employeeNumber, start_date, start_time, end_date, end_time
from
emp_data
where
employeeNumber = 123
order by
employeeNumber;
I can probably do with fetching only the first record but what would the where clause be.
Any help is appreciated as I am not very familiar with SQL Server.
This is complicated. You need to keep track of "starts" and "ends". I am going to assume that your columns are datetime
s or something similar that can be combined into a single column:
with e as (
select e.employeeNumber, v.dt, sum(v.inc) as inc,
sum(sum(v.inc)) over (partition by e.employeeNumber order by v.dt) as in_outs
from emp_data e cross apply
(values (start_date + start_time, 1),
(end_date + end_time, -1)
) v(dt, inc)
group by e.employeeNumber, v.dt
)
select employeeNumber, min(dt) as start_datetime, max(dt) as end_datetime
from (select e.*,
sum(case when in_outs = 0 then 1 else 0 end) over (partition by employeeNumber order by dt) as grp
from e
) e
where in_outs <> 0
group by employeeNumber, grp;
Here is a db<>fiddle.
What is this doing?
- First the date/times are converted to date times.
- Then the columns are unpivoted and identified as starts and ends, along with +1 or -1 to indicate whether the employee is "entering" or "existing" at that time.
- These are accumulated.
- Now you have a gaps and islands problem, where you want to find continue periods of "in"s. The "islands" are identified using a cumulative sum of "ins".
- Then these are aggregated.
EDIT:
You can replace the cumulative sum with:
from (select e.*,
(select sum(case when e2.in_outs = 0 then 1 else 0 end)
from e e2
where e2.employeeNumber = e.employeeNumber
e2.dt <= e.dt
) as grp
from e
) e
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