sql 時區時間 Local Time Zone

--時區時間 Local Time Zone Geovin Du 塗聚文
--http://www.bigresource.com/MS_SQL-Converting-UTC-datetime-values-to-local-time-zones-XDKMI9sG.html


SELECT GETUTCDATE()

SELECT GETDATE()

select CONVERT(varchar(100), GETUTCDATE(), 21)


SELECT DATEDIFF(hh,'2008-05-20 20:08:01.020', '2008-05-20 16:08:01.020')

DECLARE @UTC DATETIME
EXECUTE @UTC = UTCtoLocalDate '2008-05-20 20:08:01.020', 8
select @UTC


DECLARE @UTC DATETIME,@d varchar(100)
Set @d=CONVERT(varchar(100), GETUTCDATE(), 21)
EXECUTE @UTC = UTCtoLocalDate  @d, 8
select @UTC


--時區存儲過程 Geovin Du 塗聚文
IF EXISTS (SELECT * FROM sysobjects WHERE [name] = 'UTCtoLocalDate')
DROP PROCEDURE UTCtoLocalDate
GO
CREATE FUNCTION [dbo].[UTCtoLocalDate] 
(
 @UTCDate DATETIME,  --UTC標准時間
 @TZ INT            --時區
) 
RETURNS DATETIME AS 
BEGIN 
IF ( DATEPART(hh, @UTCDate) <> 0 ) 
BEGIN 
DECLARE @LocalDate DATETIME 
DECLARE @UTCDelta INT 
DECLARE @thisYear INT 
DECLARE @DSTDay INT 
DECLARE @NormalDay INT 
DECLARE @DSTDate DATETIME 
DECLARE @NormalDate DATETIME 
SET @thisYear = YEAR(@UTCDate) 
IF (@thisYear < 2007 ) 
 BEGIN 
  SET @DSTDay = ( 2 + 6 * @thisYear - FLOOR(@thisYear / 4) ) % 7 + 1 
  SET @NormalDay = ( 31 - ( FLOOR( @thisYear * 5 / 4) + 1) % 7) 
  SET @DSTDate = '4/' + CAST(@DSTDay AS VARCHAR(2)) + '/' + CAST(@thisYear AS VARCHAR(4)) + ' 2:00:00.000 AM' 
  SET @NormalDate = '10/' + CAST(@NormalDay AS VARCHAR(2)) + '/' + CAST(@thisYear AS VARCHAR(4)) + ' 2:00:00.000 AM' 
 END 

ELSE 
 BEGIN 
  SET @DSTDay = ( 14 - ( FLOOR( 1 + @thisYear * 5 / 4 ) ) % 7 ) 
  SET @NormalDay = ( 7 - ( FLOOR ( 1 + @thisYear * 5 / 4) ) % 7 ) 
  SET @DSTDate = '3/' + CAST(@DSTDay AS VARCHAR(2)) + '/' + CAST(@thisYear AS VARCHAR(4)) + ' 2:00:00.000 AM' 
  SET @NormalDate = '11/' + CAST(@NormalDay AS VARCHAR(2)) + '/' + CAST(@thisYear AS VARCHAR(4)) + ' 2:00:00.000 AM' 
 END
IF ((@UTCDate > @DSTDate) AND (@UTCDate < @NormalDate))
 BEGIN 
  SET @UTCDelta = @TZ + 1 
 END 
ELSE 
 BEGIN 
  SET @UTCDelta = @TZ
 END 
-- now convert utc date to local date 
SET @LocalDate = DATEADD(Hour, @UTCDelta, @UTCDate) 
END
ELSE 
 BEGIN 
  SET @LocalDate = @UTCDate 
 END 

RETURN(@LocalDate) 
END 
GO 
/*
常用的几个时区： 
GMT:Greenwich Mean Time 
ET:U.S. Eastern Time -5 
PST:Pacific Standard Time -8

GMT -11:00 Samoa 
GMT -10:00 U.S. Hawaiian Time 
GMT -09:30 Marquesas 
GMT -09:00 U.S. Alaska Time 
GMT -08:30 Pitcarn 
GMT -08:00 Pacific Time 
GMT -07:00 U.S. Mountain Time 
GMT -07:00 U.S. Mountain Time (Arizona) 
GMT -06:00 U.S. Central Time 
GMT -06:00 Mexico 
GMT -05:00 U.S. Eastern Time 
GMT -05:00 U.S. Eastern Time (Indiana) 
GMT -05:00 Columbia, Peru, South America 
GMT -04:00 Atlantic Time 
GMT -03:30 Newfoundland, Canada 
GMT -03:00 Argentina 
GMT -03:00 Brazil 
GMT -02:00 Mid-Atlantic 
GMT -01:00 Azores 
GMT U.K., Spain 
GMT +01:00 Western Europe 
GMT +02:00 Eastern Europe 
GMT +02:00 Egypt 
GMT +02:00 Israel 
GMT +03:00 Russia 
GMT +03:00 Saudi Arabia 
GMT +03:30 Iran 
GMT +04:00 Arabian 
GMT +04:30 Afghanistan 
GMT +05:00 Pakistan, West Asia 
GMT +05:30 India 
GMT +06:00 Bangladesh, Central Asia 
GMT +06:30 Burma 
GMT +07:00 Bangkok, Hanoi, Jakarta 
GMT +08:00 China, Taiwan 
GMT +08:00 China, beijing
GMT +08:00 Singapore 
GMT +08:00 Australia (WT) 
GMT +09:00 Japan 
GMT +09:00 Korea 
GMT +09:30 Australia (CT) 
GMT +10:00 Australia (ET) 
GMT +10:30 Australia (Lord Howe) 
GMT +11:00 Central Pacific 
GMT +11:30 Norfolk Islands 
GMT +12:00 Fiji, New Zealand
*/