Oracle中实现中文字符串的首字母简拼转换

/**
 *实现中文字符串的首字母简拼转换
 *@in i_str nvarchar2 要转换的字符串
 *@return result varchar2 返回值
 */
create or replace function CHS2Short(i_str in nvarchar2) return varchar2 is
  c1       varchar2(5);
  c2       varchar2(2);
  p        number(6);
  n1       integer;
  n2       integer;
  result   varchar2(32767);
begin

p:=length(i_str);
--dbms_output.put_line(i_str||':'||p);
for i in 1..p
loop
c2:=substr(i_str,i,1);
n1:=floor(ascii(c2)/256);
n2:=mod(ascii(c2),256);
if n1=0 and n2<=129 then c1:=c2;
elsif n2<>127 and n2<>255 and not (n2 between 0 and 63)
then
select  case 
when c2>='丂' and c2<'芭'then 'A'　
when c2>='芭' and c2<'擦'then 'B'
when c2>='擦' and c2<'搭'then 'C'
when c2>='搭' and c2<'蛾'then 'D'
when c2>='蛾' and c2<'发'then 'E'
when c2>='发' and c2<'噶'then 'F'
when c2>='噶' and c2<'哈'then 'G'
when c2>='哈' and c2<'击'then 'H'
when c2>='击' and c2<'喀'then 'J'
when c2>='喀' and c2<'垃'then 'K'
when c2>='垃' and c2<'妈'then 'L'
when c2>='妈' and c2<'拿'then 'M'
when c2>='拿' and c2<'哦'then 'N'
when c2>='哦' and c2<'啪'then 'O'
when c2>='啪' and c2<'期'then 'P'
when c2>='期' and c2<'然'then 'Q'
when c2>='然' and c2<'撒'then 'R'
when c2>='撒' and c2<'塌'then 'S'
when c2>='塌' and c2<'挖'then 'T'
when c2>='挖' and c2<'稀'then 'W'
when c2>='稀' and c2<'压'then 'X'
when c2>='压' and c2<'匝'then 'Y'
when c2>='匝' and c2<='鼱' then 'Z'
end
into c1 
from dual;
else
c1:='error';
end if;
result:=result||c1;
end loop;
dbms_output.put_line(i_str||':'||result);
return result;
end CHS2Short;
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