-----获取某月的第一天
create function get_Firstday(@days datetime)
returns datetime
begin
return cast(cast(year(@days) as char(4))+'-'+ cast(month(@days) as nvarchar(2))+'-01' as datetime)
end
-----获取某月的最后一天
create function get_Lastday(@days datetime)
returns datetime
begin
return dateadd(day,-1,dbo.get_firstday(dateadd(month,1,@days)))
end
----获取某月的长度
create function get_days(@days datetime)
returns int
begin
return datediff(day,dbo.get_firstday(@days),dbo.get_lastday(@days))+1
end
---获取某月的周末数
create function get_weekdays(@days datetime)
returns int
begin
declare @ret int;
declare @weekday int;
declare @leftdays int;
set @weekday=datepart(weekday,dbo.get_firstday(@days));
set @leftdays=dbo.get_days(@days) % 7
if @leftdays=0 return 8; -----28天的周末只有8天
if @leftdays=1
begin
if @weekday=7 or @weekday=1
return 9
else
return 8
end
if @leftdays=2
begin
if @weekday=7
return 10
else if @weekday=1 or @weekday=6
return 9
else
return 8
end
if @leftdays=3
begin
if @weekday=6 or @weekday=7
return 10
else if @weekday=1 or @weekday=5
return 9
else
return 8
end
return 0
end
