自动生成拼音检索码 函数

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作者：
版本：1.0
创建时间：
修改时间：
功能：自动生成 检索码(拼音码）
参数：汉字拼音
输出：拼音检索汉字
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---------自动生成 检索码(拼音码)
/****** Object:  UserDefinedFunction [dbo].[fun_getPY]    
   Script Date: 12/09/2014 21:01:21 ******/
SET ANSI_NULLS OFF
GO
SET QUOTED_IDENTIFIER OFF
GO

ALTER function [dbo].[fun_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 '' end)
  set @str=right(@str,len(@str)-1)  end  return @PY  end