最简单的答案并不总是在底部，但这一次是，并且可以在上面的评论中看到。 使用您自己的“AT TIME ZONE”来捕获列/数据字段的TzOffset，而不是当前的SYSDATETIME。 在下面的数据中，2个查询，一个关于feb数据(DST是关闭的，在阿姆斯特丹的冬天)+1差异 第二次查询阿姆斯特丹4月份的数据，所以+2小时的差异。

    select top 2 month(receiveTimeUTC) as MonthInWinterOrSpring
   ,  receiveTimeUTC
   ,  CONVERT(datetime,  SWITCHOFFSET(CONVERT(datetimeoffset,  receiveTimeUTC),  DATENAME(TzOffset, SYSDATETIMEOFFSET()))) as LocalTimeWrongNoDST
   ,  CONVERT(datetime,  SWITCHOFFSET(CONVERT(datetimeoffset,  receiveTimeUTC),  DATENAME(TzOffset, receiveTimeUTC  AT TIME ZONE 'Central European Standard Time' ))) as LocalTimeWithDST
       from sensordetails order by id

    select top 2 month(receiveTimeUTC) as MonthInWinterOrSpring, receiveTimeUTC
,  CONVERT(datetime,  SWITCHOFFSET(CONVERT(datetimeoffset,  receiveTimeUTC),  DATENAME(TzOffset, SYSDATETIMEOFFSET()))) as LocalTimeWrongNoDST
,  CONVERT(datetime,  SWITCHOFFSET(CONVERT(datetimeoffset,  receiveTimeUTC),  DATENAME(TzOffset, receiveTimeUTC  AT TIME ZONE 'Central European Standard Time' ))) as LocalTimeWithDST
       from sensordetails order by id desc

结果:

所以这是一个T-SQL (SQL Server Answer)，不需要函数的storedproc。

这些对我来说都没用，但下面这个100%有效。希望这能帮助其他像我一样尝试转换它的人。

CREATE FUNCTION [dbo].[fn_UTC_to_EST]
(
    @UTC datetime,
    @StandardOffset int
)
RETURNS datetime
AS
BEGIN

declare 
    @DST datetime,
    @SSM datetime, -- Second Sunday in March
    @FSN datetime  -- First Sunday in November
-- get DST Range
set @SSM = DATEADD(dd,7 + (6-(DATEDIFF(dd,0,DATEADD(mm,(YEAR(GETDATE())-1900) * 12 + 2,0))%7)),DATEADD(mm,(YEAR(GETDATE())-1900) * 12 + 2,0))+'02:00:00' 
set @FSN = DATEADD(dd, (6-(DATEDIFF(dd,0,DATEADD(mm,(YEAR(GETDATE())-1900) * 12 + 10,0))%7)),DATEADD(mm,(YEAR(GETDATE())-1900) * 12 + 10,0)) +'02:00:00'

-- add an hour to @StandardOffset if @UTC is in DST range
if @UTC between @SSM and @FSN
    set @StandardOffset = @StandardOffset + 1

-- convert to DST
set @DST = dateadd(hour,@StandardOffset,@UTC)

-- return converted datetime
return @DST

END

罗恩的回答有一个错误。它使用当地时间凌晨2:00，其中需要UTC等效值。我没有足够的声望分数来评论Ron的回答，所以更正版本如下:

-- =============================================
-- Author:      Ron Smith
-- Create date: 2013-10-23
-- Description: Converts UTC to DST
--              based on passed Standard offset
-- =============================================
CREATE FUNCTION [dbo].[fn_UTC_to_DST]
(
    @UTC datetime,
    @StandardOffset int
)
RETURNS datetime
AS
BEGIN

declare 
    @DST datetime,
    @SSM datetime, -- Second Sunday in March
    @FSN datetime  -- First Sunday in November
-- get DST Range
set @SSM = datename(year,@UTC) + '0314' 
set @SSM = dateadd(hour,2 - @StandardOffset,dateadd(day,datepart(dw,@SSM)*-1+1,@SSM))
set @FSN = datename(year,@UTC) + '1107'
set @FSN = dateadd(second,-1,dateadd(hour,2 - (@StandardOffset + 1),dateadd(day,datepart(dw,@FSN)*-1+1,@FSN)))

-- add an hour to @StandardOffset if @UTC is in DST range
if @UTC between @SSM and @FSN
    set @StandardOffset = @StandardOffset + 1

-- convert to DST
set @DST = dateadd(hour,@StandardOffset,@UTC)

-- return converted datetime
return @DST

END

这可以在没有函数的情况下完成。下面的代码将把UTC时间转换为考虑夏令时的山地时间。相应地调整所有的-6和-7数字到您的时区(即对于EST，您将分别调整为-4和-5)

--Adjust a UTC value, in the example the UTC field is identified as UTC.Field, to account for daylight savings time when converting out of UTC to Mountain time.
CASE
    --When it's between March and November, it is summer time which is -6 from UTC
    WHEN MONTH ( UTC.Field ) > 3 AND MONTH ( UTC.Field ) < 11 
        THEN DATEADD ( HOUR , -6 , UTC.Field )
    --When its March and the day is greater than the 14, you know it's summer (-6)
    WHEN MONTH ( UTC.Field ) = 3
        AND DATEPART ( DAY , UTC.Field ) >= 14 
        THEN
            --However, if UTC is before 9am on that Sunday, then it's before 2am Mountain which means it's still Winter daylight time.
            CASE 
                WHEN DATEPART ( WEEKDAY , UTC.Field ) = 1 
                    AND UTC.Field < '9:00'
                    --Before 2am mountain time so it's winter, -7 hours for Winter daylight time
                    THEN DATEADD ( HOUR , -7 , UTC.Field )
                --Otherwise -6 because it'll be after 2am making it Summer daylight time
                ELSE DATEADD ( HOUR , -6 , UTC.Field )
            END
    WHEN MONTH ( UTC.Field ) = 3
        AND ( DATEPART ( WEEKDAY , UTC.Field ) + 7 ) <= DATEPART ( day , UTC.Field ) 
        THEN 
            --According to the date, it's moved onto Summer daylight, but we need to account for the hours leading up to 2am if it's Sunday
            CASE 
                WHEN DATEPART ( WEEKDAY , UTC.Field ) = 1 
                    AND UTC.Field < '9:00'
                    --Before 9am UTC is before 2am Mountain so it's winter Daylight, -7 hours
                    THEN DATEADD ( HOUR , -7 , UTC.Field )
                --Otherwise, it's summer daylight, -6 hours
                ELSE DATEADD ( HOUR , -6 , UTC.Field )
            END
    --When it's November and the weekday is greater than the calendar date, it's still Summer so -6 from the time
    WHEN MONTH ( UTC.Field ) = 11
        AND DATEPART ( WEEKDAY , UTC.Field ) > DATEPART ( DAY , UTC.Field ) 
        THEN DATEADD ( HOUR , -6 , UTC.Field )
    WHEN MONTH ( UTC.Field ) = 11
        AND DATEPART ( WEEKDAY , UTC.Field ) <= DATEPART ( DAY , UTC.Field ) 
            --If the weekday is less than or equal to the calendar day it's Winter daylight but we need to account for the hours leading up to 2am.
            CASE 
                WHEN DATEPART ( WEEKDAY , UTC.Field ) = 1 
                    AND UTC.Field < '8:00'
                    --If it's before 8am UTC and it's Sunday in the logic outlined, then it's still Summer daylight, -6 hours
                    THEN DATEADD ( HOUR , -6 , UTC.Field )
                --Otherwise, adjust for Winter daylight at -7
                ELSE DATEADD ( HOUR , -7 , UTC.Field )
            END
    --If the date doesn't fall into any of the above logic, it's Winter daylight, -7
    ELSE
        DATEADD ( HOUR , -7 , UTC.Field )
END

第一个功能:配置为意大利时区(+1，+2)，切换日期:3月和10月的最后一个星期天，返回当前时区与datetime的差值作为参数。

Returns:
current timezone < parameter timezone ==> +1
current timezone > parameter timezone ==> -1
else 0

代码是:

CREATE FUNCTION [dbo].[UF_ADJUST_OFFSET]
(
    @dt_utc datetime2(7)
)
RETURNS INT
AS
BEGIN


declare @month int,
        @year int,
        @current_offset int,
        @offset_since int,
        @offset int,
        @yearmonth varchar(8),
        @changeoffsetdate datetime2(7)

declare @lastweek table(giorno datetime2(7))

select @current_offset = DATEDIFF(hh, GETUTCDATE(), GETDATE())

select @month = datepart(month, @dt_utc)

if @month < 3 or @month > 10 Begin Set @offset_since = 1 Goto JMP End

if @month > 3 and @month < 10 Begin Set @offset_since = 2 Goto JMP End

--If i'm here is march or october
select @year = datepart(yyyy, @dt_utc)

if @month = 3
Begin

Set @yearmonth = cast(@year as varchar) + '-03-'

Insert Into @lastweek Values(@yearmonth + '31 03:00:00.000000'),(@yearmonth + '30 03:00:00.000000'),(@yearmonth + '29 03:00:00.000000'),(@yearmonth + '28 03:00:00.000000'),
                         (@yearmonth + '27 03:00:00.000000'),(@yearmonth + '26 03:00:00.000000'),(@yearmonth + '25 03:00:00.000000')

--Last week of march
Select @changeoffsetdate = giorno From @lastweek Where  datepart(weekday, giorno) = 1

    if @dt_utc < @changeoffsetdate 
    Begin 
        Set @offset_since = 1 
    End Else Begin
        Set @offset_since = 2
    End
End

if @month = 10
Begin

Set @yearmonth = cast(@year as varchar) + '-10-'

Insert Into @lastweek Values(@yearmonth + '31 03:00:00.000000'),(@yearmonth + '30 03:00:00.000000'),(@yearmonth + '29 03:00:00.000000'),(@yearmonth + '28 03:00:00.000000'),
                         (@yearmonth + '27 03:00:00.000000'),(@yearmonth + '26 03:00:00.000000'),(@yearmonth + '25 03:00:00.000000')

--Last week of october
Select @changeoffsetdate = giorno From @lastweek Where  datepart(weekday, giorno) = 1

    if @dt_utc > @changeoffsetdate 
    Begin 
        Set @offset_since = 1 
    End Else Begin
        Set @offset_since = 2
    End
End

JMP:

if @current_offset < @offset_since Begin
    Set @offset = 1
End Else if @current_offset > @offset_since Set @offset = -1 Else Set @offset = 0

Return @offset

END

然后是转换日期的函数

CREATE FUNCTION [dbo].[UF_CONVERT]
(
    @dt_utc datetime2(7)
)
RETURNS datetime
AS
BEGIN

    declare @offset int


    Select @offset = dbo.UF_ADJUST_OFFSET(@dt_utc)

    if @dt_utc >= '9999-12-31 22:59:59.9999999'
        set @dt_utc = '9999-12-31 23:59:59.9999999'
    Else
        set @dt_utc = (SELECT DATEADD(mi, DATEDIFF(mi, GETUTCDATE(), GETDATE()), @dt_utc) )

    if @offset <> 0
        Set @dt_utc = dateadd(hh, @offset, @dt_utc)

    RETURN @dt_utc

END

这很简单。试试这个Azure SQL Server:

SELECT YourDateTimeColumn AT TIME ZONE 'Eastern Standard Time' FROM YourTable

对于本地SQL Server:

SELECT CONVERT(datetime2, SWITCHOFFSET(CONVERT(datetimeoffset, gETDATE()), DATENAME(TzOffset, gETDATE() AT TIME ZONE 'Eastern Standard Time'))) FROM YourTable