Sqlserver DateTime轉換成SMALLDATETIME時“產生一個超出范圍的值”

工作中遇到一個問題,A表中字段(DateTime1)的數據類型為DateTime,新建了一張表B的SMALLDATETIME1字段的數據來自A表的DateTime1

但在將A表字段DateTime1導出到B表的 SMALLDATETIME1字段時出現了以下錯誤

后經過排查發現在原來是A表 DateTime1字段的值有許多是"1753-01-01 00:00:00.000",從而導致轉換失敗

雖然知道了是什么原因導致的,但還是不太明白為什么"1753-01-01"無法轉換成SMALLDATETIME類型

通過以下兩篇文章知道DateTime與smalldatetime的差別(smalldatetime僅Sqlserver2005以上版本支持,2005不支持)

DateTime時間范圍"1753-01-01 00:00:00.000"到"9999-12-31 23:59:59.997"     

smalldatetime時間范圍"1900-01-01 00:00:00"到"2079-06-06 23:59:00"

 

MSDN datetime and smalldatetime

datetime

Date and time data from January 1, 1753 through December 31, 9999, to an accuracy of one three-hundredth of a second (equivalent to 3.33 milliseconds or 0.00333 seconds). Values are rounded to increments of .000, .003, or .007 seconds, as shown in the table.

smalldatetime

Date and time data from January 1, 1900, through June 6, 2079, with accuracy to the minute. smalldatetime values with 29.998 seconds or lower are rounded down to the nearest minute; values with 29.999 seconds or higher are rounded up to the nearest minute.

Date and time types in SQL Server

As of SQL Server 2008, we have several new types related to date and time: 

--如果存儲過程存在,則刪除重建
IF EXISTS(select1from sys.objects where type='p' AND name='HTL_Convent_DateTime')
DROP PROCEDURE HTL_Convent_DateTime;
--必須加上Go,否則下面創建存儲過程時會出現錯誤"MSSQL 'CREATE/ALTER PROCEDURE' 必須是查詢批次中的第一個語句。"
GO
--對輸入的日期進行各種日期格式轉換
--HLT
--'2014-07-30 15:12:17'
CREATE PROCEDURE HTL_Convent_DateTime
@date_time DATETIME
AS
BEGIN
SELECT @date_time AS 'DateTime',
CAST (@date_time AS DATETIME2) AS 'DateTime2'
, CAST (@date_time AS DATE) AS 'DATE'
, CAST (@date_time AS TIME) AS 'TIME'
, CAST (@date_time AS datetimeoffset) AS 'datetimeoffset'
SELECT CAST (@date_time AS SMALLDATETIME)AS 'SMALLDATETIME';
END
GO

1900-01-01之前的日期無法從DateTime轉換成smalldatetime, smalldatetime時間范圍"1900-01-01 00:00:00"到"2079-06-06 23:59:00"

2076-06-06以后的日期也無法轉換

在 smalldatetime時間范圍內的日期

DECLARE @date DATETIME
SET @date='1753-01-01 00:00:00.000'
SELECT CAST (@date AS SMALLDATETIME);

 

 

參考：

http://www.karaszi.com/SQLServer/info_datetime.asp#DtInSqlServer

http://technet.microsoft.com/en-us/library/aa258277(v=sql.80).aspx

http://www.cnblogs.com/dxmdiy/archive/2012/11/01/2749800.html