Oracle常用命令笔记

一.基础SQL语句

查：select * from employees;
增：insert into employees (Name , Birthday , Location , Salary) values ('hyddd','1984-10-1','guangzhou',999999);
改：update employees set Salary=999999999 where Name='hyddd';
删：delete from employees where name='zhangsan';
更多技巧请参考：SQL基本语句

二.PFile，SPFile管理

SPFile->PFile：
##用生成对应SID的spfile生成pfile，生成的pfile位置：$ORACLE_HOME/dbs/init$ORACLE_SID.ora
SQL> create pfile from spfile;
--------
##自己指定生成文件的位置
SQL> create pfile='/home/oracle/initorcl.ora' from spfile;

PFile->SPFile
SQL> create spfile from pfile;

三.启动，关闭数据库

启动

SQL>startup

关闭

SQL>shutdown normal
SQL>shutdown transactional
SQL>shutdown immediate
SQL>shutdown abort

四.修改SGA参数

修改SGA的原则

sga_target <= sga_max_size

SGA加上PGA等其他进程占用的内存必须少于机器物理内存。

命令

SQL>alter system set sga_max_size=2048m scope=spfile;
SQL>alter system set sga_target=2048m scope=spfile;
##修改SGA的相关参数，只能spfile，然后重启数据库。不能直接scope=both!

[b]五.查询Oracle配置参数[/b]

命令

SQL>show parameter;

具体查询某个Oracle参数，只需输入部分关键字即可，比如：查询sga_target的值。

SQL> show parameter sga;

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
lock_sga boolean FALSE
pre_page_sga boolean FALSE
sga_max_size big integer 2G
sga_target big integer 2G
SQL>

六.生成AWR报告

具体请参考《AWR报告生成》。

七.管理Oracle Enterprise Manager

查询OEM状态

emctl status dbconsole

启动OEM

emctl start dbconsole

关闭OEM

emctl stop dbconsole

八.redo logfile管理

日志切换时间间隔查询

SELECT to_char(b.first_time, 'YYYY-MM-DD HH24:MI:SS') as swtich_time, (b.first_time - a.first_time) * 24 as "switch_interval(hr)" FROM v$log_history a, v$log_history b WHERE a.SEQUENCE# + 1 = b.SEQUENCE# ORDER BY SWTICH_TIME;
--------
##前一百条记录（反序）
SELECT to_char(b.first_time, 'YYYY-MM-DD HH24:MI:SS') as swtich_time, (b.first_time - a.first_time) * 24 as "switch_interval(hr)" FROM v$log_history a, v$log_history b WHERE a.SEQUENCE# + 1 = b.SEQUENCE# AND ROWNUM <= 100 ORDER BY SWTICH_TIME desc;

查询当前的日志设置情况
SQL> col MEMBER for a40
SQL> select * From v$logfile;

GROUP# STATUS TYPE MEMBER IS_
---------- ------- -------------------- ---------------------------------------- ---
1 ONLINE /u01/app/oracle/oradata/ORA10G/redo01.log NO
2 ONLINE /u01/app/oracle/oradata/ORA10G/redo02.log NO
3 ONLINE /u01/app/oracle/oradata/ORA10G/redo03.log NO
SQL>select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
1 1 13690 52428800 1 NO CURRENT 192645086 10-FEB-09
2 1 13689 52428800 1 YES INACTIVE 192633926 10-FEB-09
3 1 13688 52428800 1 YES INACTIVE 192614912 10-FEB-09
添加两个临时日志组
SQL> alter database add logfile group 4 ('/u01/app/oracle/oradata/ORA10G/redo04.log') size 200M;
SQL> alter database add logfile group 5 ('/u01/app/oracle/oradata/ORA10G/redo05.log') size 200M;
将当前的Online Redo Log切换到新增的Redo log group上
SQL> alter system switch logfile;
SQL> alter system switch logfile;

//检查是否已经切换到新增的Online Redo log group上:
SQL> select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
1 1 13695 52428800 1 YES INACTIVE 192653667 10-FEB-09
2 1 13694 52428800 1 YES INACTIVE 192653616 10-FEB-09
3 1 13693 52428800 1 YES INACTIVE 192653593 10-FEB-09
4 1 13696 209715200 1 NO CURRENT 192653673 10-FEB-09
5 1 13692 209715200 1 YES INACTIVE 192653549 10-FEB-09
删除原来的Online Redo Logs
SQL> alter database drop logfile group 1;
SQL> alter database drop logfile group 2;
SQL> alter database drop logfile group 3;

//然后需要手动在对应目录下，手动删除redo logfile文件。
SQL> !
[oracle@orcal-50 ~]$ cd /u01/app/oracle/oradata/ORA10G/
[oracle@orcal-50 ORA10G]$rm -rf redo01.log
[oracle@orcal-50 ORA10G]$rm -rf redo02.log
[oracle@orcal-50 ORA10G]$rm -rf redo03.log

九.归档（Archive）控制

查询归档状态
SQL> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 940
Current log sequence 942
开启归档
SQL> shutdown immediate
SQL> startup mount
SQL> alter database archivelog
SQL> alter database open
关闭归档
SQL> shutdown immediate
SQL> startup mount
SQL> alter database noarchivelog
SQL> alter database open

十.查询Oracle数据库管理员

select username from dba_users;