MYSQL索引

创建索引：

create index index_birth on student.stu(stuBirth desc) using btree;
create index index_idscore on student.score(stuID,score);

alter table stu add index index_birth(stuBirth desc);
alter table score add index index_idscore (stuID,score);

create table teacher (teaId int not null primary key,teaName varchar(30) not null,teaSchool varchar(50) not null,index index_name (teaName(3)));
create table teacher (teaId int not null ,teaName varchar(30) not null,teaSchool varchar(50) not null,index index_nane (teaName(3)),primary key(teaID));

查看索引：

show index from stu from student;
show index from teacher from student;

删除索引：

drop index index_name on teacher;
alter table teacher drop primary key;``