mysql存储过程问题？？

[hongming271]

mysql中写了一段存储过程，举个例子，我数据库中有两个值一个是“001”，另一个是“餐饮软件名”，我分别传这两个值，其中“001”返回的值‘001A’，而“餐饮软件名”返回的是一个“null”,现在想请教大家，怎样让我的“餐饮软件名”返回的值是“餐饮软件名A”

top: BEGIN	
DECLARE  tableid   INTEGER;
DECLARE  aliasint  INTEGER;  
DECLARE  count_setup   INTEGER;   
DECLARE  alias_long  varchar(400);   
DECLARE  alias  VARCHAR(1) DEFAULT 'A';  
DECLARE errorcode INTEGER DEFAULT 0 ;  

if  ( ta_abbre is null )  then    	 return ( null ) ; 
end if;
BEGIN
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION  SET errorcode = 1 ; 
select table_id into tableid from tw_table where table_abbre=ta_abbre;
END; 
if (tableid is null ) then return ( null  );
end if;
BEGIN
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION  SET errorcode = 1 ;
select  group_concat(right(table_alias,1))  into  alias_long from dc_ordermaptable where table_id=tableid and is_hang=0 group by table_id;
END;
if  ( alias_long is null ) then return ( concat( ta_abbre , 'A' ));
else
set aliasint=65 ;
set alias = char( aliasint );
flag: while aliasint <=69  and aliasint >=65 do
if (  POSITION( alias  IN  alias_long) = 0 ) then
leave flag;
end if;
set aliasint = aliasint +1 ;
set alias = char( aliasint );
end while;
end if;
if ( ascii ( alias )> 69 ) then return ( null  ) ;
end if;
return ( concat( ta_abbre , alias  ));END

[rucypli]

在select concat执行前先执行set names gbk;