t-sql - 计算每行日期之间的差异

Question

你能说明如何在t-sql中完成这项工作吗？

样本记录

accountnumber trandate
-------------------------
1000          02-11-2010
1000          02-12-2010
1000          02-13-2010
2000          02-10-2010
2000          02-15-2010

如何计算每个帐号的每笔交易之间的天数？ 像这样

accountnumber trandate       # of days
----------------------------------------
1000          02-11-2010       0
1000          02-12-2010       1
1000          02-13-2010       1
2000          02-10-2010       0
2000          02-15-2010       5

非常感谢！

Answer 1

SELECT accountnumber, 
       trandate, 
       Datediff(DAY, a.trandate, (SELECT TOP 1 trandate 
                                  FROM   mytable b 
                                  WHERE  b.trandate > a.trandate 
                                  ORDER  BY trandate)) 
FROM   mytable a 
ORDER  BY trandate 

Answer 2

您可以使用between and

select * from table1 where trandate  between 'date1' and 'date2'

Answer 3

希望这有帮助。

Select A.AccountNo, A.TranDate, B.TranDate as PreviousTranDate, A.TranDate - B.Trandate as NoOfDays
from
(Select AccountNo, TranDate, Row_Number() as RNO over (Partition by AccountNo order by TranDate)) as A, 
(Select AccountNo, TranDate, Row_Number() as RNO over (Partition by AccountNo order by TranDate)) as B
Where A.AccountNo = B.AccountNo and A.RNO -1  = B.RNO

您还可以使用CTE表达式来提高性能。