在mysql 里实现查询汉字的拼音首字母

1、建立拼音首字母资料表

DROP   TABLE   IF   EXISTS   `pyk`;   
  CREATE   TABLE   `pyk`   (   
      `PY`   varchar(1)    ,   
      `HZ1`   int  ,
      `HZ2`   int      
  ) ;
   
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),
('I',-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),              
('V',-13318,-12839),              
('W',-12838,-12557),              
('X',-12556,-11848),              
('Y',-11847,-11056),              
('Z',-11055,-10247);

2、建立mysql 函数

DROP FUNCTION IF EXISTS hzcode;

delimiter //

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
//

delimiter ;

3、先测试一下
mysql> select hzcode('南海龙王');
+--------------------+
| hzcode('南海龙王') |
+--------------------+
| N                  |
+--------------------+
1 row in set (0.00 sec)
4、建立个测试表

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

insert into f1(name) values
('张三'),
('李四'),
('王五'),
('赵六'),
('钱七');

5、测试
mysql> select * from f1;
+------+-------+
| name | pykey |
+------+-------+
| 张三 | NULL  |
| 李四 | NULL  |
| 王五 | NULL  |
| 赵六 | NULL  |
| 钱七 | NULL  |
+------+-------+
5 rows in set (0.00 sec)

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

mysql> select * from f1;
+------+-------+
| name | pykey |
+------+-------+
| 张三 | Z     |
| 李四 | L     |
| 王五 | W     |
| 赵六 | Z     |
| 钱七 | Q     |
+------+-------+
5 rows in set (0.00 sec)


这样就很方便地在MYSQL里查询汉字的首字母了。 类似地也可以直接在MYSQL得到汉字拼音。 不过需要拼音表，函数写法也不一样。