1alter database：修改数据文件

alter database datafile 4 offline;

alter database datafile '/opt/oracle/datafile/users01.dbf' offline;

alter database datafile '/opt/oracle/datafile/users01.dbf' resize 100M;

alter database datafile '/opt/oracle/datafile/users01.dbf' autoextend on next 100M maxsize 1000M;

alter database datafile 4 end backup;

2alter database：修改临时文件(tempfile)

alter database tempfile 4 resize 100M;

alter database tempfile 4 autoextend on next 100M maxsize 1000M;

alter database tempfile 4 drop including datafiles;

alter database tempfile 4 offline;

3alter database：归档日志(archivelog)模式命令

alter database archivelog;

alter database noarchivelog;

alter database force logging;

alter database clear logfile '/opt/oracle/logfiles/redo01.rdo';

alter database clear unarchived logfile '/opt/oracle/logfiles/redo01.rdo';

alter database add supplemental log data;

alter database add supplemental log data (primary key,unique);

alter database drop supplemental log data;

4alter database：控制文件操作

alter database backup controlfile to trace;

alter database backup controlfile to trace as '/opt/oracle/logfile_backup/backup_logfile.trc' reuse resetlogs;

alter database backup controlfile to '/opt/oracle/logfile_backup/backup_logfile.ctl';

5alter database：创建数据文件

alter database create datafile '/opt/oracle/datafile/users01.dbf' as '/opt/oracle/datafile/users01.dbf';

alter database create datafile 4 as '/opt/oracle/datafile/users01.dbf';

alter database create datafile '/opt/oracle/datafile/users01.dbf' as new;

6alter database：日志文件命令

alter database add logfile group 2 ('/opt/oracle/logfiles/redo02a.rdo','/opt/oracle/logfile/redo02b.rdo') size 300M reuse;

alter database add logfile member '/opt/oracle/logfiles/redo02c.rdo' to gourp 2

alter database add logfile thread 3 group 2 ('/opt/oracle/logfiles/redo02a.rdo','/opt/oracle/logfiles/redo02b.rdo') size 300M reuse;

alter database drop logfile group 3

alter database drop logfile member '/opt/oracle/logfiles/redo02b.rdo';

7alter database：安装和打开数据库

alter database mount;

alter database open;

8alter database：移动或重命名数据库文件或联机重做日志

注意：数据库必须已经安装才能重命名或移动联机重做日志。数据库必须已经安装或数据文件处于脱机状态时，才能移动数据库中的数据文件。

alter database rename file '/ora/datafile/oldfile.dbf' to '/ora/datafile/newfile.dbf';

9alter database：以只读方式打开数据库

alter database open read only;

10alter database：使用resetlogs打开数据

alter database open resetlogs;

11alter database：恢复数据库

对数据库的恢复，建议使用recover命令代替。