一.表空间的创建1.创建普通表空间指定初始大小,自动扩展,最大大小:(Oracle允许的单个smallfile数据文件最大大小为 4194302*bl
一.表空间的创建
1.创建普通表空间指定初始大小,自动扩展,最大大小:
(Oracle允许的单个smallfile数据文件最大大小为 4194302*blocksize,单个bigfile数据文件最大可达到(32-128)TB)
(默认创建表空间为标准的8k数据块,smallfile表空间)
create tablespace t1 datafile '/u01/oracle/product/oradata/orcl/t1.dbf' size 10m autoextend on next 5m maxsize 100m;
2.创建非标准块大小的表空间:
alter system set db_16k_cache_size=100m scope=spfile;
shutdown immediate;
startup;
create tablespace t2 datafile '/u01/oracle/product/oradata/orcl/t2.dbf' size 10m blocksize 16k;
3.创建大文件表空间(大文件表空间只允许有一个数据文件):
create bigfile tablespace t3 datafile '/u01/oracle/product/oradata/orcl/t3.dbf' size 10m ;
二.修改表空间(如果修改临时表空间,,注意将语句中的datafile改为tempfile):
1.在表空间中添加数据文件:
alter tablespace t1 add datafile '/u01/oracle/product/oradata/orcl/t11.dbf' size 1m;
2.在表空间中删除数据文件:
alter tablespace t1 drop datafile '/u01/oracle/product/oradata/orcl/t11.dbf';
3.修改指定数据文件的大小
alter database datafile '/u01/oracle/product/oradata/orcl/t1.dbf' resize 1m;
三。表空间与数据文件的offline与online
1.表空间的脱机与联机
alter tablespace t1 offline;
alter tablespace t1 online;
2.数据文件的脱机与联机(数据文件的脱机与联机需要使用归档模式,数据文件脱机后一定要执行数据文件介质恢复,否则会报错)
shutdown immediate;
startup mount;
alter database archivelog;
alter database open;
alter database datafile '/u01/oracle/product/oradata/orcl/t1.dbf' offline;
recover datafile 5;
alter database datafile '/u01/oracle/product/oradata/orcl/t1.dbf' online;
四。表空间改名
alter tablespace t1 rename to t4;
五.表空间删除
1。正常删除表空间,不删除数据文件:
drop tablespace t4 ;
2.删除表空间同时删除所有相关数据文件;
drop tablespace t2 including contents and datafiles;
六。使用已经存在但未使用的数据文件创建表空间:
SQL> create tablespace t1 datafile '/u01/oracle/product/oradata/orcl/t1.dbf' size 10m;
create tablespace t1 datafile '/u01/oracle/product/oradata/orcl/t1.dbf' size 10m
*
ERROR at line 1:
ORA-01119: error in creating database file
'/u01/oracle/product/oradata/orcl/t1.dbf'
ORA-27038: created file already exists
Additional information: 1
SQL> create tablespace t1 datafile '/u01/oracle/product/oradata/orcl/t1.dbf' reuse;
Tablespace created.

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