sqlServer 获取汉字字串的拼音声母

CREATE function fGetPy(@str varchar(500)='') 
returns varchar(500) 
as 
begin 
declare @strlen int,@return varchar(500),@ii int 
declare @c nchar(1),@chn nchar(1) 
select @strlen=len(@str),@return='',@ii=0 
set @ii=0 
while @ii<@strlen 
begin 
select @ii=@ii+1,@chn=substring(@str,@ii,1) 
if @chn>='吖' 
select @c = char(count(*)+63) from ( 
select top 27 * from ( 
select chn = '吖' 
union all select '八' 
union all select '嚓' 
union all select '咑' 
union all select '妸' 
union all select '发' 
union all select '旮' 
union all select '铪' 
union all select '丌' --because have no 'i' 
union all select '丌' 
union all select '咔' 
union all select '垃' 
union all select '嘸' 
union all select '拏' 
union all select '噢' 
union all select '妑' 
union all select '七' 
union all select '呥' 
union all select '仨' 
union all select '他' 
union all select '屲' --no 'u' 
union all select '屲' --no 'v' 
union all select '屲' 
union all select '夕' 
union all select '丫' 
union all select '帀' 
union all select @chn 
) as a 
order by chn COLLATE Chinese_PRC_CI_AS ) as b 
where b.chn <=@chn 
else set @c=@chn 
set @return=@return+@c 
end 
return(@return) 
end