在MySQL中是允许在同一个列上创建多个索引的,示例如下:
mysql --socket=/tmp/mysql5173.sock -uroot -p
mysql> SELECT VERSION();
+-----------+
| VERSION() |
+-----------+
| 5.1.73 |
+-----------+
1 row in set (0.00 sec)
# 创建测试表
mysql> DROP TABLE temp;
ERROR 1051 (42S02): Unknown table 'temp'
mysql> CREATE TABLE temp
-> (id int auto_increment primary key,
-> name varchar(20),
-> password varchar(20),
-> age int) ENGINE=INNODB DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (0.12 sec)
# 插入测试数据
mysql> INSERT INTO temp(name, password, age)
VALUES('robin', '123456', '18');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO temp(name, password, age)
VALUES('jack', '123456', '19');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO temp(name, password, age)
VALUES('rose', '123456', '20'