mysql索引类型介绍

建表：
creat table student(
 stu_id int unsigned not null auto_increment,
 name varchar(32) not null default '',
 phone char(11) not null default '',
 stu_code varchar(32) not null default '',
 stu_desc text,
 primary key ('stu_id'), //主键索引
 unique index 'stu_code' ('stu_code'), //唯一索引
 index 'name_phone' ('name','phone'), //普通索引，复合索引
 fulltext index 'stu_desc' ('stu_desc'), //全文索引) engine=myisam charset=utf8;

更新：
alert table student add primary key ('stu_id'), //主键索引
 add unique index 'stu_code' ('stu_code'), //唯一索引
 add index 'name_phone' ('name','phone'), //普通索引，复合索引
 add fulltext index 'stu_desc' ('stu_desc'); //全文索引删除：
alert table sutdent
 drop primary key,
 drop index 'stu_code',
 drop index 'name_phone',
 drop index 'stu_desc';