MYSQL數據庫DROP TABLE IF EXISTS `pyk`;
CREATE TABLE `pyk` (
`PY` varchar(1) ,
`HZ1` int ,
`HZ2` int
) ;

MYSQL數據庫INSERT INTO `pyk` (`PY`,`HZ1`,`HZ2`) VALUES
('A',-20319,-20284),
('B',-20283,-19776),
('C',-19775,-19219),
('D',-19218,-18711),
('E',-18710,-18527),
('F',-18526,-18240),
('G',-18239,-17923),
('H',-17922,-17418),
('J',-17417,-16475),
('K',-16474,-16213),
('L',-16212,-15641),
('M',-15640,-15166),
('N',-15165,-14923),
('O',-14922,-14915),
('P',-14914,-14631),
('Q',-14630,-14150),
('R',-14149,-14091),
('S',-14090,-13319),
('T',-13318,-12839),
('W',-12838,-12557),
('X',-12556,-11848),
('Y',-11847,-11056),
('Z',-11055,-10247);
?

MYSQL數據庫DROP FUNCTION IF EXISTS hzcode;

MYSQL數據庫delimiter //

MYSQL數據庫CREATE FUNCTION hzcode (s CHAR(255)) RETURNS char
BEGIN
DECLARE hz_code int;
DECLARE hz_py char;
SET hz_code = ord(substring(s,1,1))*256+ord(substring(s,2,1))-65536 ;
select py into hz_py from pyk where hz_code>=pyk.hz1 and hz_code<=pyk
.hz2;
RETURN hz_py;
END
//

MYSQL數據庫delimiter ;
數 據庫類型如果是GBK的時候,這個函數好像有點小問題,稍微改動了下,貌似可以在GBK中使用了

MYSQL數據庫delimiter $$
DROP FUNCTION IF EXISTS `hzcode`$$
CREATE FUNCTION `hzcode` (s CHAR(255)) RETURNS char
BEGIN
DECLARE hz_code int;
DECLARE hz_py char;
declare str varchar(400);
SET hz_code = ord(substring(s,1,1))-65536 ;
select py into hz_py from pyk where hz_code>=pyk.hz1 and hz_code<=pyk.hz2;
RETURN hz_py;

MYSQL數據庫END$$
delimiter $$
?

mysql> select hzcode('南海龍王');
+--------------------+
| hzcode('南海龍王') |
+--------------------+
| N |
+--------------------+
1 row in set (0.00 sec)

MYSQL數據庫DROP TABLE IF EXISTS `f1`;
create table f1 (
name varchar(30),
pykey varchar(1)
);

MYSQL數據庫insert into f1(name) values
('張三'),
('李四'),
('王五'),
('趙六'),
('錢七');
?

MYSQL數據庫mysql> select * from f1;
+------+-------+
| name | pykey |
+------+-------+
| 張三 | NULL |
| 李四 | NULL |
| 王五 | NULL |
| 趙六 | NULL |
| 錢七 | NULL |
+------+-------+
5 rows in set (0.00 sec)

MYSQL數據庫mysql> update f1 set pykey = hzcode(name);
Query OK, 5 rows affected (0.05 sec)
Rows matched: 5 Changed: 5 Warnings: 0

MYSQL數據庫mysql> select * from f1;
+------+-------+
| name | pykey |
+------+-------+
| 張三 | Z |
| 李四 | L |
| 王五 | W |
| 趙六 | Z |
| 錢七 | Q |
+------+-------+
5 rows in set (0.00 sec)