标签：style color strong ar for 数据 2014 div 问题
数据库日期和时间类型
相互转换
time ? date
time ? smalldatetime
time ? datetime
time ? datetime2
time ? datetimeoffset
date ? smalldatetime
date ? datetime
date ? datetime2
date ? datetimeoffset
smalldatetime ? datetime
smalldatetime ? datetime2
smalldatetime ? datetimeoffset
datetime ? datetime2
datetime ? datetimeoffset
datetime2 ? datetimeoffset
数据库日期和时间类型：
|
类型 |
格式 |
范围 |
|
time |
hh:mm:ss[.nnnnnnn] | 00:00:00.0000000 ~ 23:59:59.9999999 |
|
date |
YYYY-MM-DD | 0001-01-01 ~ 9999-12-31 |
|
smalldatetime |
YYYY-MM-DD hh:mm:ss | 1900-01-01 ~ 079-06-06 |
|
datetime |
YYYY-MM-DD hh:mm:ss[.nnn] | 1753-01-01 ~ 99-12-31 |
|
datetime2 |
YYYY-MM-DD hh:mm:ss[.nnnnnnn] | 0001-01-01 00:00:00.0000000 ~ 99-12-31 23:59:59.9999999 |
|
datetimeoffset |
YYYY-MM-DD hh:mm:ss[.nnnnnnn] [+|-]hh:mm | 0001-01-01 00:00:00.0000000 ~9999-12-31 23:59:59.9999999 (in UTC) |
相互转换（SET DATEFORMAT dmy;）
time ? date
1: -- time -> date
2: DECLARE @time time(4) = ‘12:15:04.1234‘;
3: DECLARE @date date= @time;
4:
5: SELECT @time AS ‘@time‘, @date AS ‘@date‘;
Result：
Operand type clash: time is incompatible with date
1: -- date -> time
2: DECLARE @date date= ‘12-10-25‘;
3: DECLARE @time time= @date;
4:
5: SELECT @date AS ‘@date‘, @time AS ‘@time‘;
Result：
Operand type clash: time is incompatible with date
time ? smalldatetime
1: -- time -> smalldatetime
2: DECLARE @time time(4) = ‘12:15:04.1234‘;
3: DECLARE @smalldatetime smalldatetime= @time;
4:
5: SELECT @time AS ‘@time‘, @smalldatetime AS ‘@smalldatetime‘;
Result：
@time @smalldatetime
12:15:04.1234 1900-01-01 12:15:00
1: -- samlldatetime –> time
2: DECLARE @smalldatetime smalldatetime = ‘13-12-1995 12:43:10‘;
3: DECLARE @time time(4) = @smalldatetime;
4:
5: SELECT @smalldatetime AS ‘@smalldatetime‘, @time AS ‘time‘;
Result：
@smalldatetime @time
1995-12-13 12:43:00 12:43:00.0000
time ? datetime
1: -- time -> datetime
2: DECLARE @time time(4) = ‘12:10:05.1234‘;
3: DECLARE @datetime datetime = @time;
4:
5: SELECT @time AS ‘@datetime‘, @datetime AS ‘@time‘;
Result：
@time @datetime
12:10:05.1234 1900-01-01 12:10:05.123
1: -- datetime -> time
2: DECLARE @datetime datetime = ‘12-11-05 12:10:05.123‘;
3: DECLARE @time time(4) = @datetime;
4:
5: SELECT @datetime AS ‘@datetime‘, @time AS ‘@time‘;
Result：
@datetime @time
2005-11-12 12:10:05.123 12:10:05.1230
time ? datetime2
1: -- time -> datetime2
2: DECLARE @time time(4) = ‘12:15:04.1234‘;
3: DECLARE @datetime2 datetime2(3) = @time;
4:
5: SELECT @datetime2 AS ‘@datetime2‘, @time AS ‘@time‘;
Result：
@time @datetime2
12:15:04.1234 1900-01-01 12:15:04.123
1: -- datetime2 -> time
2: DECLARE @datetime2 datetime2(4) = ‘12-10-25 12:32:10.1234‘;
3: DECLARE @time time(3) = @datetime2;
4:
5: SELECT @datetime2 AS ‘@datetime2‘, @time AS ‘@time(3)‘;
Result：
@datetime2 @time(3)
2025-10-12 12:32:10.1234 12:32:10.123
time ? datetimeoffset
1: -- time -> datetimeoffset
2: DECLARE @time time(4) = ‘12:15:04.1234‘;
3: DECLARE @datetimeoffset datetimeoffset(3) = @time;
4:
5: SELECT @time AS ‘@time‘, @datetimeoffset AS ‘@datetimeoffset‘;
Result：
@time @datetimeoffset
12:15:04.1234 1900-01-01 12:15:04.123 +00:00
1: -- datetimeoffset -> time
2: DECLARE @datetimeoffset datetimeoffset(4) = ‘12-10-25 12:32:10.1234 +01:0‘;
3: DECLARE @time time(3) = @datetimeoffset;
4:
5: SELECT @datetimeoffset AS ‘@datetimeoffset ‘, @time AS ‘@time‘;
Result：
@datetimeoffset @time
2025-10-12 12:32:10.1234 +01:00 12:32:10.123
date ? smalldatetime
1: -- date -> smalldatetime
2: DECLARE @date date= ‘1912-10-25‘;
3: DECLARE @smalldatetime smalldatetime = @date;
4:
5: SELECT @date AS ‘@date‘, @smalldatetime AS ‘@smalldatetime‘;
Result：
@date @smalldatetime
1912-10-25 1912-10-25 00:00:00
1: -- smalldatetime -> date
2: DECLARE @smalldatetime smalldatetime = ‘13-12-1955 12:43:10‘;
3: DECLARE @date date = @smalldatetime
4:
5: SELECT @smalldatetime AS ‘@smalldatetime‘, @date AS ‘@date‘;
Result：
@smalldatetime @date
1955-12-13 12:43:00 1955-12-13
date ? datetime
1: -- date -> datetime
2: DECLARE @date date= ‘12-10-25‘;
3: DECLARE @datetime datetime= @date;
4:
5: SELECT @date AS ‘@date‘, @datetime AS ‘@datetime‘;
Result：
@date @datetime
2025-10-12 2025-10-12 00:00:00.000
1: -- datetime -> date
2: DECLARE @datetime datetime = ‘12-11-05 12:43:10‘;
3: DECLARE @date date = @datetime;
4:
5: SELECT @datetime AS ‘@datetime‘, @date AS ‘@date‘;
Result：
@datetime @date
2005-11-12 12:43:10.000 2005-11-12
date ? datetime2
1: -- date -> datetime2
2: DECLARE @date date = ‘25-10-2030‘
3: DECLARE @datetime2 datetime2(3) = @date;
4:
5: SELECT @date AS ‘@date‘, @datetime2 AS ‘@datetime2(3)‘;
Result：
@date @datetime2(3)
2030-10-25 2030-10-25 00:00:00.000
1: -- datetime2 -> date
2: DECLARE @datetime2 datetime2(4) = ‘12-10-25 12:32:10.1234‘;
3: DECLARE @date date = @datetime2;
4:
5: SELECT @datetime2 AS ‘@datetime2‘, @date AS ‘@date‘;
Result：
@datetime2 @date
2025-10-12 12:32:10.1234 2025-10-12
date ? datetimeoffset
1: -- date -> datetimeoffset
2: DECLARE @date date = ‘1912-10-25‘;
3: DECLARE @datetimeoffset datetimeoffset(3) = @date;
4:
5: SELECT @date AS ‘@date‘, @datetimeoffset AS ‘@datetimeoffset‘;
Result：
@date @datetimeoffset
1912-10-25 1912-10-25 00:00:00.000 +00:00
1: -- datetimeoffset -> date
2: DECLARE @datetimeoffset datetimeoffset(4) = ‘12-10-25 12:32:10 +01:0‘;
3: DECLARE @date date= @datetimeoffset;
4:
5: SELECT @datetimeoffset AS ‘@datetimeoffset ‘, @date AS ‘@date‘;
Result：
@datetimeoffset @date
2025-10-12 12:32:10.0000 +01:00 2025-10-12
smalldatetime ? datetime
1: -- smalldatetime -> datetime
2: DECLARE @smalldatetime smalldatetime = ‘12-10-2040 12:43:10‘;
3: DECLARE @datetime datetime = @smalldatetime;
4:
5: SELECT @smalldatetime AS ‘@smalldatetime‘, @datetime AS ‘@datetime‘;
Result：
@smalldatetime @datetime
2040-10-12 12:43:00 2040-10-12 12:43:00.000
1: -- datetime -> smalldatetime
2: DECLARE @datetime datetime = ‘12-11-05 12:43:10.123‘;
3: DECLARE @smalldatetime smalldatetime = @datetime;
4:
5: SELECT @datetime AS ‘datetime‘, @smalldatetime AS ‘@smalldatetime‘;
Result：
datetime @smalldatetime
2005-11-12 12:43:10.123 2005-11-12 12:43:00
smalldatetime ? datetime2
1: -- smalldatetime -> datetime2
2: DECLARE @smalldatetime smalldatetime = ‘12-06-2011 12:43:10‘;
3: DECLARE @datetime2 datetime2(4) = @smalldatetime;
4:
5: SELECT @smalldatetime AS ‘@smalldatetime‘, @datetime2 AS ‘@datetime2(4)‘;
Result：
@smalldatetime @datetime2(4)
2011-06-12 12:43:00 2011-06-12 12:43:00.0000
1: -- datetime2 -> smalldatetime
2: DECLARE @datetime2 datetime2 = ‘12-10-25 12:32:10.1234567‘;
3: DECLARE @smalldatetime smalldatetime = @datetime2;
4:
5: SELECT @datetime2 AS ‘@datetime2‘, @smalldatetime AS ‘@smalldatetime‘;
Result：
@datetime2 @smalldatetime
2025-10-12 12:32:10.1234567 2025-10-12 12:32:00
smalldatetime ? datetimeoffset
1: -- samlldatetime -> datetimeoffset
2: DECLARE @smalldatetime smalldatetime = ‘12-10-2013 12:43:10‘;
3: DECLARE @datetimeoffset datetimeoffset(4) = @smalldatetime;
4:
5: SELECT @smalldatetime AS ‘@smalldatetime‘, @datetimeoffset AS ‘@datetimeoffset(4)‘;
Result：
@smalldatetime @datetimeoffset(4)
2013-10-12 12:43:00 2013-10-12 12:43:00.0000 +00:00
1: -- datetimeoffset -> smalldatetime
2: DECLARE @datetimeoffset datetimeoffset(3) = ‘1912-10-25 12:24:32 +10:0‘;
3: DECLARE @smalldatetime smalldatetime = @datetimeoffset;
4:
5: SELECT @datetimeoffset AS ‘@datetimeoffset‘, @smalldatetime AS ‘@smalldatetime‘;
Result：
@datetimeoffset @smalldatetime
1912-10-25 12:24:32.000 +10:00 1912-10-25 12:25:00
datetime ? datetime2
1: -- datetimes -> datetime2
2: DECLARE @datetime datetime = ‘10-10-2014 12:45:37.123‘;
3: DECLARE @datetime2 datetime2(4) = @datetime;
4:
5: SELECT @datetime AS ‘@datetime‘, @datetime2 AS ‘@datetime2‘;
Result：
@datetime @datetime2
2014-10-10 12:45:37.123 2014-10-10 12:45:37.1230
1: -- datetimes2 -> datetime
2: DECLARE @datetime2 datetime2(4) = ‘1968-10-23 12:45:37.1237‘;
3: DECLARE @datetime datetime = @datetime2;
4:
5: SELECT @datetime2 AS ‘@datetime2‘, @datetime AS ‘@datetime‘;
Result：
@datetime2 @datetime
1968-10-23 12:45:37.1237 1968-10-23 12:45:37.123
datetime ? datetimeoffset
1: -- datetime -> datetimeoffset
2: DECLARE @datetime datetime = ‘12-10-25 12:32:10.123‘;
3: DECLARE @datetimeoffset datetimeoffset = @datetime;
4:
5: SELECT @datetime AS ‘@datetime ‘, @datetimeoffset AS ‘@datetimeoffset‘;
Result：
@datetime @datetimeoffset
2025-10-12 12:32:10.123 2025-10-12 12:32:10.1230000 +00:00
1: -- datetimeoffset -> datetime
2: DECLARE @datetimeoffset datetimeoffset(4) = ‘12-10-25 12:32:10.1234 +01:0‘;
3: DECLARE @datetime datetime = @datetimeoffset;
4:
5: SELECT @datetimeoffset AS ‘@datetimeoffset ‘, @datetime AS ‘@datetime‘;
Result：
@datetimeoffset @datetime
2025-10-12 12:32:10.1234 +01:00 2025-10-12 12:32:10.123
datetime2 ? datetimeoffset
1: -- datetime2 -> datetimeoffset
2: DECLARE @datetime2 datetime2(3) = ‘12-10-25 12:32:10.1234567‘;
3: DECLARE @datetimeoffset datetimeoffset(2) = @datetime2;
4:
5: SELECT @datetime2 AS ‘@datetime2‘, @datetimeoffset AS ‘@datetimeoffset(2)‘;
Result：
@datetime2 @datetimeoffset(2)
2025-10-12 12:32:10.123 2025-10-12 12:32:10.12 +00:00
1: -- datetimeoffset -> datetime2
2: DECLARE @datetimeoffset datetimeoffset(4) = ‘1912-10-25 12:24:32.1234 +10:0‘;
3: DECLARE @datetime2 datetime2(3)= @datetimeoffset;
4:
5: SELECT @datetimeoffset AS ‘@datetimeoffset‘, @datetime2 AS ‘@datetime2‘;
Result：
@datetimeoffset @datetime2
1912-10-25 12:24:32.1234 +10:00 1912-10-25 12:24:32.123
在此谢谢读完这篇博客，有什么写的不对的地方请指正。
有帮助就推荐下，有感想就写下留言，不满意也写下留言，有问题及时更正。
标签：style color strong ar for 数据 2014 div 问题
原文地址：http://www.cnblogs.com/sand-tiny/p/3946005.html
