sql得到中文首字母

USE [JewelryRetailClientDB]
GO

/****** Object:  UserDefinedFunction [dbo].[Func_GetPY]    Script Date: 10/19/2011 14:21:59 ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

-- =============================================
-- Author:        xoyozo
-- Create date: 2010-4-17
-- Description:    提供中文首字母
-- =============================================
CREATE FUNCTION [dbo].[Func_GetPY]
(
    @str NVARCHAR(4000)
)
RETURNS NVARCHAR(4000)
AS
BEGIN
    DECLARE @word NCHAR(1),@PY NVARCHAR(4000)
    SET @PY=''
    WHILE len(@str)>0
    BEGIN
        SET @word=left(@str,1)
        SET @PY=@PY+(CASE WHEN unicode(@word) BETWEEN 19968 AND 19968+20901
        THEN (SELECT TOP 1 PY FROM (
        SELECT 'A' AS PY,N'驁' AS word
        UNION ALL SELECT 'B',N'簿'
        UNION ALL SELECT 'C',N'錯'
        UNION ALL SELECT 'D',N'鵽'
        UNION ALL SELECT 'E',N'樲'
        UNION ALL SELECT 'F',N'鰒'
        UNION ALL SELECT 'G',N'腂'
        UNION ALL SELECT 'H',N'夻'
        UNION ALL SELECT 'J',N'攈'
        UNION ALL SELECT 'K',N'穒'
        UNION ALL SELECT 'L',N'鱳'
        UNION ALL SELECT 'M',N'旀'
        UNION ALL SELECT 'N',N'桛'
        UNION ALL SELECT 'O',N'漚'
        UNION ALL SELECT 'P',N'曝'
        UNION ALL SELECT 'Q',N'囕'
        UNION ALL SELECT 'R',N'鶸'
        UNION ALL SELECT 'S',N'蜶'
        UNION ALL SELECT 'T',N'籜'
        UNION ALL SELECT 'W',N'鶩'
        UNION ALL SELECT 'X',N'鑂'
        UNION ALL SELECT 'Y',N'韻'
        UNION ALL SELECT 'Z',N'咗'
        ) T 
        WHERE word>=@word COLLATE Chinese_PRC_CS_AS_KS_WS 
        ORDER BY PY ASC) ELSE @word END)
        SET @str=right(@str,len(@str)-1)
    END
    RETURN @PY
END
GO