获取一个模糊查询

set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go

ALTER FUNCTION [dbo].[GetFirstAlpha]
 (
 @str nvarchar(4000)
 )
returns nvarchar(4000)
AS
 BEGIN
 declare @strlen int,@re nvarchar(4000)
declare @t table(chr nchar(1) collate Chinese_PRC_CI_AS,letter nchar(1))
insert into @t(chr,letter)
  select '吖','A' union all select '八','B' union all
  select '嚓','C' union all select '咑','D' union all
  select '妸','E' union all select '发','F' union all
  select '旮','G' union all select '铪','H' union all
  select '丌','J' union all select '咔','K' union all
  select '垃','L' union all select '嘸','M' union all
  select '拏','N' union all select '噢','O' union all
  select '妑','P' union all select '七','Q' union all
  select '呥','R' union all select '仨','S' union all
  select '他','T' union all select '屲','W' union all
  select '夕','X' union all select '丫','Y' union all
  select '帀','Z'
  select @strlen=len(@str),@re=''
  while @strlen>0
  begin
    select top 1 @re=letter+@re,@strlen=@strlen-1
      from @t a where chr<=substring(@str,@strlen,1)
      order by chr desc
    if @@rowcount=0
      select @re=substring(@str,@strlen,1)+@re,@strlen=@strlen-1
  end
  return(@re)
 END