DECLARE @nowDate DATETIME = '2000-03-04'
 
SELECT DATEDIFF(
    DAY,
    [dbo].[svf_FirstDateOfTheYear](@nowDate),
    [dbo].[svf_LastDateOfTheYear](@nowDate)
) + 1

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天数
-- =============================================
CREATE FUNCTION [dbo].[svf_DaysOfTheYear]
( 
    @TheYear DATETIME 
)
RETURNS INT
AS
BEGIN
    RETURN DATEDIFF(
    DAY,
    [dbo].[svf_FirstDateOfTheYear](@TheYear),
    [dbo].[svf_LastDateOfTheYear](@TheYear)
) + 1
END