c#-更新满足datediff约束的所有行的int列?
作者:互联网
我有一个每30秒运行一次的函数,我想更新当前时间所在的所有行中的一列-table.lastStoredTime> 5分钟.
lastStoredTime是datetime列,我似乎无法正常工作.
尝试(不更新行)
SELECT
DATEDIFF(MINUTE, t.lastStoredTime, CURRENT_TIMESTAMP) AS Mtime
FROM Transaction_tbl t
WHERE
AND DATEDIFF(MINUTE,t.lastStoredTime, CURRENT_TIMESTAMP) > 5
解决方法:
测试设置:
create table Transaction_tbl (id int identity(1,1) not null, lastStoredTime datetime2(7), intcol int)
insert into Transaction_tbl
select dateadd(minute,-7,sysdatetime()), 0
union all select dateadd(minute,-6,sysdatetime()), 0
union all select dateadd(minute,-5,sysdatetime()), 0
union all select dateadd(minute,-4,sysdatetime()), 0
union all select dateadd(minute,-3,sysdatetime()), 0
查询:
/* select */
select *,
datediff(minute, t.lastStoredTime, sysdatetime()) as Mtime
from Transaction_tbl t
where t.lastStoredTime < dateadd(minute,-5,sysdatetime())
/* as an update */
update t
set intcol = intcol+1
output inserted.*
from Transaction_tbl t
where t.lastStoredTime < dateadd(minute,-5,sysdatetime())
右手演示:http://rextester.com/TXYXT83237
选择输出:
+----+---------------------+--------+-------+
| id | lastStoredTime | intcol | Mtime |
+----+---------------------+--------+-------+
| 1 | 2017-08-22 19:31:52 | 0 | 7 |
| 2 | 2017-08-22 19:32:52 | 0 | 6 |
| 3 | 2017-08-22 19:33:52 | 0 | 5 |
+----+---------------------+--------+-------+
更新输出:
+----+---------------------+--------+
| id | lastStoredTime | intcol |
+----+---------------------+--------+
| 1 | 2017-08-22 19:31:52 | 1 |
| 2 | 2017-08-22 19:32:52 | 1 |
| 3 | 2017-08-22 19:33:52 | 1 |
+----+---------------------+--------+
使用案例表达式进行更新:
update t
set intcol = case when t.lastStoredTime < dateadd(minute,-5,sysdatetime())
then intcol+1
else intcol-1
end
output inserted.*
from Transaction_tbl t
输出:
+----+---------------------+--------+
| id | lastStoredTime | intcol |
+----+---------------------+--------+
| 1 | 2017-08-22 19:47:14 | 2 |
| 2 | 2017-08-22 19:48:14 | 2 |
| 3 | 2017-08-22 19:49:14 | -1 |
| 4 | 2017-08-22 19:50:14 | -1 |
| 5 | 2017-08-22 19:51:14 | -1 |
+----+---------------------+--------+
标签:azure-functions,timestamp,sql,c,sql-server 来源: https://codeday.me/bug/20191025/1931017.html