管理簇+创建簇索引+修改簇+删除簇

管理簇
使用的测试数据

 create cluster my_clu (deptno number )  
    pctused 40    
    pctfree 10  
    size 1024  
    tablespace myspace  
    storage (  
    initial 128 k  
    next 128 k  
    minextents 2  
    maxextents 20  
    );   


    create table dept_clu(  
    deptno number ,  
    dname varchar2 ( 20 )  
    )  
    cluster my_clu(deptno);  

    create table emp_clu(  
    empno number ,  
    ename varchar2 ( 20 ),  
    deptno number  
    )  
    cluster my_clu(deptno);  

创建簇索引
1如果没创建簇索引，无法往簇表中添加数据

insert into dept_clu values(1,'a');
create index dept_clu_index on cluster my_clu --创建簇索引
tablespace myspace;
insert into dept_clu values(1,'a');

修改簇
alter cluster cluster_name
….

    alter  cluster my_clu
    pctused 50    
    pctfree 20 

删除簇
1如果簇表存在
drop cluster cluster_name including tables;
including tables：关联的簇表也删除掉

    drop cluster my_clu;
    drop cluster my_clu including tables;

2如果簇表不存在
drop cluster cluster_name；

create cluster my_clu1 (deptno number )  
    pctused 40    
    pctfree 10  
    size 1024  
    tablespace myspace  
    storage (  
    initial 128 k  
    next 128 k  
    minextents 2  
    maxextents 20  
    );   
drop cluster my_clu1;