各位高手大大们：
小弟是oracle的初学者，想请问你们，我应该怎么看oracle的日志呢？比如，我想看看最近我都对数据库中的某个表进行了些什么操作（特别是删除操作）！不知道oracle的日志能保存今天的操作信息！谢谢！请帮忙！高分送上！
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1.系统开机、关机等信息在alert_xxx.log(bdump参数所指目录).
2.表的操作没有日志，除非你用audit或者用logMiner看arch文件，不过这些对于
初学者来说都有点困难。
3.其他的系统，无论是DB2还是SQL SERVER，系统也都不会自动去记录对表的操作。
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我想看看最近我都对数据库中的某个表进行了些什么操作
在ORACLE中還沒有這樣的功能，現在隻能做到對用戶登陸和操作的總體記錄
無法精確到對表操作的統計
如果你需要對表的操作進行統計，那就需要用到審計（audit）功能
但是審計功能會很耗費系統的資源，降低系統的性能！！
用以下的方式可以監控登入登出的用戶:
創建如下的兩張表:
create table login_log -- 登入登出信息表
(
session_id int not null, -- sessionid
login_on_time date, -- 登入時間
login_off_time date, -- 登出時間
user_in_db varchar2(30), -- 登入的db user
machine varchar2(20), -- 機器名
ip_address varchar2(20), -- ip地址
run_program varchar2(20) -- 以何程序登入
);
create table allow_user -- 網域用戶表
(
ip_address varchar2(20), -- ip地址
login_user_name nvarchar2(20) -- 操作者姓名
);
創建如下的兩個觸發器:
create or replace trigger login_on_info -- 紀錄登入信息的觸發器
after logon on database
Begin
insert into login_log(session_id,login_on_time,login_off_time,user_in_db,machine,ip_address,run_program)
select AUDSID,sysdate,null,sys.login_user,machine,SYS_CONTEXT('USERENV','IP_ADDRESS'),program
from v$session where AUDSID = USERENV('SESSIONID'); --當前SESSION
END;
create or replace trigger login_off_info -- 紀錄登出信息的觸發器
before logoff on database
Begin
update login_log set login_off_time = sysdate
where session_id = USERENV('SESSIONID'); --當前SESSION
exception
when others then
null;
END;
方法二:
用如下的方式可以審計執行drop動作的事件:
/**
- drop語句的審計日誌表
*/
create table drop_log
(
session_id int not null, -- sessionid
drop_time date, -- drop的時間
ip_address varchar2(20), -- ip地址
object_owner varchar2(30), -- 對象的擁有者
object_name varchar2(30), -- 對象名稱
object_type varchar2(20), -- 對象類型
drop_by_user varchar2(30) -- 執行drop語句的用戶
);
create or replace trigger drop_info
after drop on mfg0513user.schema -- 在mfg0513user用戶上創建審計drop的觸發器
begin
insert into drop_log
(session_id,
drop_time,
ip_address,
object_owner,
object_name,
object_type,
drop_by_user)
values(USERENV('SESSIONID'),
sysdate,
SYS_CONTEXT('USERENV','IP_ADDRESS'),
sys.dictionary_obj_owner,
sys.dictionary_obj_name,
sys.dictionary_obj_type,
sys.login_user);
end;
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论坛中有位老兄贴的，忘了是谁了~
1. 监控事例的等待
select event,sum(decode(wait_Time,0,0,1)) "Prev",
sum(decode(wait_Time,0,1,0)) "Curr",count(*) "Tot"
from v$session_Wait
group by event order by 4;
2. 回滚段的争用情况
select name, waits, gets, waits/gets "Ratio"
from v$rollstat a, v$rollname b
where a.usn = b.usn;
3. 监控表空间的 I/O 比例
select df.tablespace_name name,df.file_name "file",f.phyrds pyr,
f.phyblkrd pbr,f.phywrts pyw, f.phyblkwrt pbw
from v$filestat f, dba_data_files df
where f.file# = df.file_id
order by df.tablespace_name;
4. 监控文件系统的 I/O 比例
select substr(a.file#,1,2) "#", substr(a.name,1,30) "Name",
a.status, a.bytes, b.phyrds, b.phywrts
from v$datafile a, v$filestat b
where a.file# = b.file#;
5.在某个用户下找所有的索引
select user_indexes.table_name, user_indexes.index_name,uniqueness, column_name
from user_ind_columns, user_indexes
where user_ind_columns.index_name = user_indexes.index_name
and user_ind_columns.table_name = user_indexes.table_name
order by user_indexes.table_type, user_indexes.table_name,
user_indexes.index_name, column_position;
6. 监控 SGA 的命中率
select a.value + b.value "logical_reads", c.value "phys_reads",
round(100 * ((a.value+b.value)-c.value) / (a.value+b.value)) "BUFFER HIT RATIO"
from v$sysstat a, v$sysstat b, v$sysstat c
where a.statistic# = 38 and b.statistic# = 39
and c.statistic# = 40;
7. 监控 SGA 中字典缓冲区的命中率
select parameter, gets,Getmisses , getmisses/(gets+getmisses)*100 "miss ratio",
(1-(sum(getmisses)/ (sum(gets)+sum(getmisses))))*100 "Hit ratio"
from v$rowcache
where gets+getmisses <>0
group by parameter, gets, getmisses;
8. 监控 SGA 中共享缓存区的命中率，应该小于1%
select sum(pins) "Total Pins", sum(reloads) "Total Reloads",
sum(reloads)/sum(pins) *100 libcache
from v$librarycache;
select sum(pinhits-reloads)/sum(pins) "hit radio",sum(reloads)/sum(pins) "reload percent"
from v$librarycache;
9. 显示所有数据库对象的类别和大小
select count(name) num_instances ,type ,sum(source_size) source_size ,
sum(parsed_size) parsed_size ,sum(code_size) code_size ,sum(error_size) error_size,
sum(source_size) +sum(parsed_size) +sum(code_size) +sum(error_size) size_required
from dba_object_size
group by type order by 2;
10. 监控 SGA 中重做日志缓存区的命中率，应该小于1%
SELECT name, gets, misses, immediate_gets, immediate_misses,
Decode(gets,0,0,misses/gets*100) ratio1,
Decode(immediate_gets+immediate_misses,0,0,
immediate_misses/(immediate_gets+immediate_misses)*100) ratio2
FROM v$latch WHERE name IN ('redo allocation', 'redo copy');
11. 监控内存和硬盘的排序比率，最好使它小于 .10，增加 sort_area_size
SELECT name, value FROM v$sysstat WHERE name IN ('sorts (memory)', 'sorts (disk)');
12. 监控当前数据库谁在运行什么SQL语句
SELECT osuser, username, sql_text from v$session a, v$sqltext b
where a.sql_address =b.address order by address, piece;
13. 监控字典缓冲区
SELECT (SUM(PINS - RELOADS)) / SUM(PINS) "LIB CACHE" FROM V$LIBRARYCACHE;
SELECT (SUM(GETS - GETMISSES - USAGE - FIXED)) / SUM(GETS) "ROW CACHE" FROM V$ROWCACHE;
SELECT SUM(PINS) "EXECUTIONS", SUM(RELOADS) "CACHE MISSES WHILE EXECUTING" FROM V$LIBRARYCACHE;
后者除以前者,此比率小于1%,接近0%为好。
SELECT SUM(GETS) "DICTIONARY GETS",SUM(GETMISSES) "DICTIONARY CACHE GET MISSES"
FROM V$ROWCACHE
14. 找ORACLE字符集
select * from sys.props$ where name='NLS_CHARACTERSET';
15. 监控 MTS
select busy/(busy+idle) "shared servers busy" from v$dispatcher;
此值大于0.5时，参数需加大
select sum(wait)/sum(totalq) "dispatcher waits" from v$queue where type='dispatcher';
select count(*) from v$dispatcher;
select servers_highwater from v$mts;
servers_highwater接近mts_max_servers时，参数需加大
16. 碎片程度
select tablespace_name,count(tablespace_name) from dba_free_space group by tablespace_name
having count(tablespace_name)>10;
alter tablespace name coalesce;
alter table name deallocate unused;
create or replace view ts_blocks_v as
select tablespace_name,block_id,bytes,blocks,'free space' segment_name from dba_free_space
union all
select tablespace_name,block_id,bytes,blocks,segment_name from dba_extents;
select * from ts_blocks_v;
select tablespace_name,sum(bytes),max(bytes),count(block_id) from dba_free_space
group by tablespace_name;
查看碎片程度高的表
SELECT segment_name table_name , COUNT() extents
FROM dba_segments WHERE owner NOT IN ('SYS', 'SYSTEM') GROUP BY segment_name
HAVING COUNT() = (SELECT MAX( COUNT(*) ) FROM dba_segments GROUP BY segment_name);
17. 表、索引的存储情况检查
select segment_name,sum(bytes),count(*) ext_quan from dba_extents where
tablespace_name='&tablespace_name' and segment_type='TABLE' group by tabl