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简单介绍
在 Oracle 10g 以前的版本，更改表空间名字是几乎不可能的事情，除非删除，重新创建，大费周章。Oracle 10g 新添加了一项更改表空间名字的功能，使得更改表空间名字瞬间即可完成。是个较为人性化的功能。 SQL> COL FILE_NAME format a70
SQL> SET linesize 120 SQL> SET pagesize 99 SQL> COL TABLESPACE_NAME format a10 SQL> SQL> SELECT file_name, tablespace_name FROM dba_data_files; FILE_NAME TABLESPACE ---------------------------------------------------------------------- ---------- /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/users01.dbf USERS /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/sysaux01.dbf SYSAUX /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/undotbs01.dbf UNDOTBS1 /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/system01.dbf SYSTEM /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/example01.dbf EXAMPLE /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/foo1.dbf FOO 6 rows selected. 该命令的语法很简单: ALTER TABLESPACE tablespacename RENAME TO newtablespacename;
tablespacename 和newtablespacename 分别对应原来的表空间名字和更改后的表空间名字： 实战演练 注意：在操作前后都请做好控制文件的备份工作 SQL>ALTER TABLESPACE foo RENAME TO test;
Tablespace altered. SQL> SELECT file_name, tablespace_name FROM dba_data_files; FILE_NAME TABLESPACE ---------------------------------------------------------------------- ---------- /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/users01.dbf USERS /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/sysaux01.dbf SYSAUX /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/undotbs01.dbf UNDOTBS1 /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/system01.dbf SYSTEM /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/example01.dbf EXAMPLE /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/foo1.dbf TEST 因为 system 和 sysaux 这两个表空间的特殊性，是不可以更名的: SQL> ALTER TABLESPACE system RENAME TO mysystem;
ALTER TABLESPACE system RENAME TO mysystem * ERROR at line 1: ORA-00712: cannot rename system tablespace SQL> ALTER TABLESPACE sysaux RENAME TO mysysaux; ALTER TABLESPACE sysaux RENAME TO mysysaux * ERROR at line 1: ORA-13502: Cannot rename SYSAUX tablespace 可以对 undo tablespace 重新命名，如果使用的是 spfile ,而不是 pfile, Oracle 会自动对 spfile 中的 undo_tablespace 进行更改(不过要在数据库重新启动之后才可以观察到), 如果使用的是 pfile ,要对其进行手工更改。我们看看 spfile 的变化情况： SQL> ALTER tablespace undotbs1 RENAME TO undotbs;
Tablespace altered. SQL> SQL> show parameter pfile NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ spfile string /u01/app/oracle/product/10.1.0 /db_1/dbs/spfileTEST.ora SQL> show parameters undo NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ undo_management string AUTO undo_retention integer 900 undo_tablespace string UNDOTBS1 SQL> shutdown immediate; Database closed. Database dismounted. ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 180355072 bytes Fixed Size 777996 bytes Variable Size 128983284 bytes Database Buffers 50331648 bytes Redo Buffers 262144 bytes Database mounted. Database opened. SQL> show parameters undo NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ undo_management string AUTO undo_retention integer 900 undo_tablespace string UNDOTBS SQL> 对脱机表空间的更名是不允许的： SQL> ALTER TABLESPACE TEST OFFLINE; Tablespace altered. SQL> ALTER TABLESPACE test RENAME TO testoffline; ALTER TABLESPACE test RENAME TO testoffline * ERROR at line 1: ORA-01135: file 6 accessed for DML/query is offline ORA-01110: data file 6: '/u01/app/oracle/product/10.1.0/db_1/oradata/TEST/foo1.dbf' 给出的提示信息很有参考价值：更名操作是要对表空间进行 DML/query 操作的，表空间offline的话，则不可以。 那么如果表空间是只读的会怎么样呢？ SQL> ALTER TABLESPACE TEST ONLINE;
Tablespace altered. SQL> ALTER TABLESPACE TEST READ ONLY; Tablespace altered. SQL> ALTER TABLESPACE test RENAME TO testreadonly; Tablespace altered. SQL> list 1* SELECT file_name, tablespace_name FROM dba_data_files SQL> / FILE_NAME TABLESPACE ---------------------------------------------------------------------- ---------- /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/users01.dbf USERS /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/sysaux01.dbf SYSAUX /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/undotbs01.dbf UNDOTBS /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/system01.dbf SYSTEM /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/example01.dbf EXAMPLE /u01/app/oracle/product/10.1.0/db_1/oradata/TEST/foo1.dbf TESTREADONLY 6 rows selected. 看来数据字典已经更新，不过Oracle会向alert_SID.log 中写入类似如下的日志: ALTER TABLESPACE test RENAME TO testreadonly
Sat Nov 13 16:15:21 2004 Tablespace 'TEST' is renamed to 'TESTREADONLY'. Tablespace name change is not propagated to file headersbecause the tablespace is read only. Completed: ALTER TABLESPACE test RENAME TO testreadonly 注意Log里有个细微的小Bug：headersbecause。这是两个词，应该空开的 :-) 更名对 Bigfile 表空间一样有效。 限制条件 应用这个特性有个主要的限制条件：COMPATIBLE 初始化参数要求为 10.0 或者更高才可以 参考信息 Oracle Database Administrator's Guide 10g Release 1 (10.1) Part Number B10739-01 ( Note 62294.1 ) |
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