关于sql 循环求和问题
我有一张表
table1 (milleage,gpstime) 表是按照时间升序排列的，现在想获取milleage总和,
总和=（第2条记录的milleage-第1条记录的milleage）+（第3条记录的milleage-第2条记录的milleage）....
希望大牛们指教，谢谢！
还有不用游标如何循环一个表的记录去累加？
[解决办法]
29-12=17
[解决办法]
神啊，我的问题我都写不出来了
[解决办法]
;with cte as (
select ROW_NUMBER() OVER (ORDER BY gpstime) AS Row, abc,gpstime from Table_test
)
select sum(b.abc - a.abc)
from cte a,cte b
where a.row = b.row -1
and b.abc > a.abc
and b.abc < a.abc + 10
[解决办法]
select (select top 1 abc from tb order by gpstime desc)-(select top 1 abc from tb)
[解决办法]
模拟你的数据和脚本
--建表
create table table_Test(abc int,gpstime datetime)
insert into table_Test values (12,'20130128')
insert into table_Test values (15,'20130129')
insert into table_Test values (14,'20130130')
insert into table_Test values (25,'20130131')
insert into table_Test values (29,'20130201')
--你的脚本
select sum((b.abc-a.abc )) as abc
from (select ROW_NUMBER() OVER (ORDER BY gpstime) AS Row, abc,gpstime
from Table_test )a
join (select t.Row,abc,gpstime
from (select ROW_NUMBER() OVER (ORDER BY gpstime) AS Row, abc,gpstime
from Table_test )t
where t.Row>1)b
on a.Row = b.row-1
--结果
abc
-----------
17
(1 row(s) affected)
