取得拼音字头的存储过程_MySQL

CREATE FUNCTION NWGetPYFirst
(@str varchar(500) = '')
RETURNS varchar(500)
AS
BEGIN
Declare @strlen int,
@return varchar(500),
@ii int,
@c char(1),
@chn nchar(1)
--//初始化变量
Declare @pytable table(
chn char(2) COLLATE Chinese_PRC_CS_AS NOT NULL,
py char(1) COLLATE Chinese_PRC_CS_AS NULL,
PRIMARY KEY (chn)
)
insert into @pytable values('吖', 'A')
insert into @pytable values('八', 'B')
insert into @pytable values('嚓', 'C')
insert into @pytable values('咑', 'D')
insert into @pytable values('妸', 'E')
insert into @pytable values('发', 'F')
insert into @pytable values('旮', 'G')
insert into @pytable values('铪', 'H')
insert into @pytable values('丌', 'I')
--insert into @pytable values('丌', 'J')
insert into @pytable values('咔', 'K')
insert into @pytable values('垃', 'L')
insert into @pytable values('嘸', 'M')
insert into @pytable values('拏', 'N')
insert into @pytable values('噢', 'O')
insert into @pytable values('妑', 'P')
insert into @pytable values('七', 'Q')
insert into @pytable values('呥', 'R')
insert into @pytable values('仨', 'S')
insert into @pytable values('他', 'T')
insert into @pytable values('屲', 'U')
--insert into @pytable values('屲', 'V')
--insert into @pytable values('屲', 'W')
insert into @pytable values('夕', 'X')
insert into @pytable values('丫', 'Y')
insert into @pytable values('帀', 'Z')

select @strlen = len(@str), @return = '', @ii = 0
--//循环整个字符串,用拼音的首字母替换汉字
while @ii < @strlen
begin
select @ii = @ii 1, @chn = substring(@str, @ii, 1)
if @chn > 'z' --//检索输入的字符串中有中文字符
SELECT @c = max(py)
FROM @pytable
where chn <= @chn
else
set @c=@chn

set @return=@return @c
end
return @return
END
GO

-- =============================================
-- Example to execute function
-- =============================================
SELECT dbo.NWGetPYFirst('梦想国度'), dbo.NWGetPYFirst('noctwolf分享源码'), dbo.NWGetPYFirst('')
GO