在10g以前,要彻底删除数据库,只有两个方法,一个是利用DBCA图形化工具删除数据库,另外一个就是关闭数据库后,手工删除数据文件、控制文件以及日志文件的方法。
从10g开始,Oracle提供了DROP DATABASE的语法,使得数据库的删除变得非常的简单。
不过DROP DATABASE还是有一定的限制条件的:
SQL> conn / as sysdba
Connected.
SQL> drop database;
drop database
*
ERROR at line 1:
ORA-01586: database must be mounted EXCLUSIVE and not open for this operation
SQL> alter database close;
Database altered.
SQL> drop database;
drop database
*
ERROR at line 1:
ORA-12719: operation requires database is in RESTRICTED mode
SQL> alter system enable restricted session;
System altered.
SQL> drop database;
Database dropped.
Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
SQL> exit
[oracle@bjtest ~]$ ps -ef|grep test102
oracle 15805 14913 0 06:13 pts/1 00:00:00 grep test102
数据库必须处于MOUNT状态,且设置了RESTRICTED SESSION。执行了DROP DATABASE命令后,Oracle自动删除控制文件,已经控制文件中记录的数据文件和在线重做日志文件,如果数据库使用了SPFILE,那么SPFILE文件也会删除。这个命令不会删除归档文件和备份文件。
在alert文件中,可以看到drop database对应的操作:
drop database
Mon May 18 06:13:01 2009
Deleted file /data/oradata/test102/system01.dbf
Deleted file /data/oradata/test102/undotbs1.dbf
Deleted file /data/oradata/test102/sysaux01.dbf
Deleted file /data/oradata/test102/redo01.log
Deleted file /data/oradata/test102/redo02.log
Deleted file /data/oradata/test102/redo03.log
Deleted file /data/oradata/test102/redo04.log
Deleted file /data/oradata/test102/redo05.log
Deleted file /data/oradata/test102/redo06.log
Deleted file /data/oradata/test102/redo07.log
Deleted file /data/oradata/test102/temp01.dbf
Instance terminated by USER, pid = 15795
Deleted file /data/oradata/test102/control01.ctl
Completed: drop database
Mon May 18 06:13:08 2009
Shutting down instance (abort)
License high water mark = 1