SQL 服务器按最接近零的值排序
SQL Server order by closest value to zero
我在 table 中有一些重复的值,我正在尝试使用 Row_Number
将它们过滤掉。我想使用 datediff
对行进行排序,并根据最接近零的值对结果进行排序,但我很难解释负值。
下面是数据示例和我当前的 Row_Number
字段 (rn
) 列:
PersonID SurveyDate DischargeDate DaysToSurvey rn
93638 10/02/2015 30/03/2015 -48 1
93638 27/03/2015 30/03/2015 -3 2
250575 23/10/2014 29/10/2014 -6 1
250575 19/11/2014 24/11/2014 -5 2
203312 23/01/2015 26/01/2015 -3 1
203312 26/01/2015 26/01/2015 0 2
387737 19/02/2015 26/02/2015 -7 1
387737 26/02/2015 26/02/2015 0 2
751915 02/04/2015 04/04/2015 -2 1
751915 10/04/2015 25/03/2015 16 2
712364 24/01/2015 30/01/2015 -6 1
712364 26/01/2015 30/01/2015 -4 2
我的 select 声明是:
select
PersonID, SurveyDate, DischargeDate,
datediff(dd,dischargedate,surveydate) days,
ROW_NUMBER () over (partition by PersonID
order by datediff(dd, dischargedate, surveydate) asc) as rn
from
Table 1
order by
PersonID, rn
我想做的是更改排序顺序,使其显示如下:
PersonID SurveyDate DischargeDate DaysToSurvey rn
93638 27/03/2015 30/03/2015 -3 1
93638 10/02/2015 30/03/2015 -48 2
250575 19/11/2014 24/11/2014 -5 1
250575 23/10/2014 29/10/2014 -6 2
因此最接近 DischargeDate
的 DaysToSurvey
值排名为 rn 1。
这可能吗?
您可以使用 abs
来获取距零的距离:
select PersonID, SurveyDate, DischargeDate, datediff(dd,dischargedate,surveydate) days,
ROW_NUMBER () over (partition by PersonID order by abs(datediff(dd,dischargedate,surveydate)) asc) as rn
from Table 1
order by PersonID, rn
你很接近。只需添加 ABS()
来计算差异的绝对值:
ROW_NUMBER () OVER (
PARTITION BY PersonID
ORDER BY abs(datediff(dd, dischargedate, surveydate)) asc
) AS rn
添加 ABS():
select PersonID, SurveyDate, DischargeDate, datediff(dd,dischargedate,surveydate) days,
ROW_NUMBER () over (partition by PersonID order by ABS(datediff(dd,dischargedate,surveydate)) asc) as rn
from Table 1
order by PersonID, rn
我在 table 中有一些重复的值,我正在尝试使用 Row_Number
将它们过滤掉。我想使用 datediff
对行进行排序,并根据最接近零的值对结果进行排序,但我很难解释负值。
下面是数据示例和我当前的 Row_Number
字段 (rn
) 列:
PersonID SurveyDate DischargeDate DaysToSurvey rn
93638 10/02/2015 30/03/2015 -48 1
93638 27/03/2015 30/03/2015 -3 2
250575 23/10/2014 29/10/2014 -6 1
250575 19/11/2014 24/11/2014 -5 2
203312 23/01/2015 26/01/2015 -3 1
203312 26/01/2015 26/01/2015 0 2
387737 19/02/2015 26/02/2015 -7 1
387737 26/02/2015 26/02/2015 0 2
751915 02/04/2015 04/04/2015 -2 1
751915 10/04/2015 25/03/2015 16 2
712364 24/01/2015 30/01/2015 -6 1
712364 26/01/2015 30/01/2015 -4 2
我的 select 声明是:
select
PersonID, SurveyDate, DischargeDate,
datediff(dd,dischargedate,surveydate) days,
ROW_NUMBER () over (partition by PersonID
order by datediff(dd, dischargedate, surveydate) asc) as rn
from
Table 1
order by
PersonID, rn
我想做的是更改排序顺序,使其显示如下:
PersonID SurveyDate DischargeDate DaysToSurvey rn
93638 27/03/2015 30/03/2015 -3 1
93638 10/02/2015 30/03/2015 -48 2
250575 19/11/2014 24/11/2014 -5 1
250575 23/10/2014 29/10/2014 -6 2
因此最接近 DischargeDate
的 DaysToSurvey
值排名为 rn 1。
这可能吗?
您可以使用 abs
来获取距零的距离:
select PersonID, SurveyDate, DischargeDate, datediff(dd,dischargedate,surveydate) days,
ROW_NUMBER () over (partition by PersonID order by abs(datediff(dd,dischargedate,surveydate)) asc) as rn
from Table 1
order by PersonID, rn
你很接近。只需添加 ABS()
来计算差异的绝对值:
ROW_NUMBER () OVER (
PARTITION BY PersonID
ORDER BY abs(datediff(dd, dischargedate, surveydate)) asc
) AS rn
添加 ABS():
select PersonID, SurveyDate, DischargeDate, datediff(dd,dischargedate,surveydate) days,
ROW_NUMBER () over (partition by PersonID order by ABS(datediff(dd,dischargedate,surveydate)) asc) as rn
from Table 1
order by PersonID, rn