获取指定日期所属年份的第一天日期或最后一天日期

写了2个自定义函数，获取指定日期所在年份的第一天日期或最后一天的日期：

 

set ansi_nulls on
go
set quoted_identifier on
go
-- =============================================
-- author:      insus.net
-- create date: 2019-05-09
-- update date: 2019-05-09
-- description: 获取指定日期所属年份的第一天日期
-- =============================================
create function [dbo].[svf_firstdateoftheyear]
( 
    @theyear datetime 
)
returns datetime
as
begin
    return  dateadd(year,datediff(year,0,@theyear),0)  
end

go

 

 

set ansi_nulls on
go
set quoted_identifier on
go
-- =============================================
-- author:      insus.net
-- create date: 2019-05-09
-- update date: 2019-05-09
-- description: 获取指定日期所属年份的最后一天日期
-- =============================================
create function [dbo].[svf_lastdateoftheyear]
( 
    @theyear datetime 
)
returns datetime
as
begin
    return dateadd(day,-1,dateadd(year,datediff(year,0,@theyear) + 1,0))
end
go

 

举例说明：