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备注：
一、 常用的数据字典：
dba_data_files:通常用来查询关于数据库文件的信息
dba_db_links:包括数据库中的所有数据库链路，也就是databaselinks。
dba_extents:数据库中所有分区的信息
dba_free_space:所有表空间中的自由分区
dba_indexs:关于数据库中所有索引的描述
dba_ind_columns:在所有表及聚集上压缩索引的列
dba_objects:数据库中所有的对象
dba_rollback_segs:回滚段的描述
dba_segments:所有数据库段分段的存储空间
dba_synonyms:关于同义词的信息查询
dba_@R_301_5991@s:数据库中所有数据表的描述
dba_tabespaces:关于表空间的信息
dba_tab_columns:所有表描述、视图以及聚集的列
dba_tab_grants/privs:对象所授予的权限
dba_ts_quotas:所有用户表空间限额
dba_users:关于数据的所有用户的信息
dba_vIEws:数据库中所有视图的文本
二、常用的动态性能视图：
v$database: 数据库信息
v$datafile：数据库使用的数据文件信息
v$librarycache：共享池中SQL语句的管理信息
v$lock：通过访问数据库会话，设置对象锁的所有信息
v$log：从控制文件中提取有关重做日志组的信息
v$logfile有关实例重置日志组文件名及其位置的信息
v$parameter：初始化参数文件中所有项的值
v$process：当前进程的信息
v$rollname：回滚段信息
v$rollstat：联机回滚段统计信息
v$rowcache：内存中数据字典活动/性能信息
v$session:有关会话的信息
v$sesstat：在v$session中报告当前会话的统计信息
v$sqlarea：共享池中使用当前光标的统计信息，光标是一块内存区域，有Oracle处理SQL语句时打开。
v$statname：在v$sesstat中报告各个统计的含义
v$sysstat：基于当前操作会话进行的系统统计
v$waitstat：出现一个以上会话访问数据库的数据时的详细情况。当有一个以上的会话访问同一信息时，可出现等待情况。
三、查询用户信息
1、查看数据库实例
select * from v$database;
2、查询所有用户信息(解锁状态,表空间等)
select * from dba_users;
3、查询当前用户信息
select * from dba_ustats;
4、 查看当前用户的角色
sql>select * from user_role_privs;
5、 查看当前用户的系统权限和表级权限
sql>select * from user_sys_privs;
sql>select * from user_tab_privs;
6、 查看当前用户的缺省表空间
sql>select username,default_@R_301_5991@space from user_users;
7、 查看用户下所有的表
sql>select * from user_@R_301_5991@s;
sql>select * from dba_@R_301_5991@s where owner='大写用户名字';
8、 查看用户下所有的表的列属性
sql>select * from USER_TAB_ColUMNS where @R_301_5991@_name=:@R_301_5991@_name;
9、 显示当前会话所具有的权限
sql>select * from session_privs;
10、 显示指定用户所具有的系统权限
sql>select * from dba_sys_privs where grantee='GAME';
11、 显示特权用户
select * from v$pwfile_users;
二、查询表
1、 查看用户下所有的表
sql>select * from user_@R_301_5991@s;
2、 查看名称包含log字符的表
sql>select object_name,object_ID from user_objects
where instr(object_name,'LOG')>0;
3、 查看某表的创建时间
sql>select object_name,created from user_objects where object_name=upper('&@R_301_5991@_name');
4、 查看某表的大小
sql>select sum(bytes)/(1024*1024) as "size(M)" from user_segments
where segment_name=upper('&@R_301_5991@_name');
5、 查看放在Oracle的内存区里的表
sql>select @R_301_5991@_name,cache from user_@R_301_5991@s where instr(cache,'Y')>0;
三、 查看索引信息
1、 查看索引个数和类别
sql>select index_name,index_type,@R_301_5991@_name from user_indexes order by @R_301_5991@_name;
2、 查看索引被索引的字段
sql>select * from user_ind_columns where index_name=upper('&index_name');
3、 查看索引的大小
sql>select sum(bytes)/(1024*1024) as "size(M)" from user_segments
where segment_name=upper('&index_name');
4 序列号
1、 查看序列号，last_number是当前值
sql>select * from user_sequences;
四、查看视图
1、 查看视图的名称
sql>select vIEw_name from user_vIEws;
2、 查看创建视图的select语句
sql>set vIEw_name,text_length from user_vIEws;
sql>set long 2000; 说明：可以根据视图的text_length值设定set long 的大小
sql>select text from user_vIEws where vIEw_name=upper('&vIEw_name');
五、同义词
1、 查看同义词的名称
sql>select * from user_synonyms;
六、约束条件
1、 查看某表的约束条件
sql>select constraint_name,constraint_type,search_condition,r_constraint_name
from user_constraints where @R_301_5991@_name = upper('&@R_301_5991@_name');
sql>select c.constraint_name,c.constraint_type,cc.column_name
from user_constraints c,user_cons_columns cc
where c.owner = upper('&@R_301_5991@_owner') and c.@R_301_5991@_name = upper('&@R_301_5991@_name')
and c.owner = cc.owner and c.constraint_name = cc.constraint_name
order by cc.position;
七、存储函数和过程
1、 查看函数和过程的状态
sql>select object_name,status from user_objects where object_type='FUNCTION';
sql>select object_name,0);">user_objects where object_type='PROCEDURE';
2、 查看函数和过程的源代码
sql>select text from all_source where owner=user and name=upper('&plsql_name')；
八、常用SQL查询：
1、查看表空间的名称及大小
select t.@R_301_5991@space_name,round(sum(bytes/(1024*1024)),0) ts_size
from dba_@R_301_5991@spaces t,dba_data_files d
where t.@R_301_5991@space_name = d.@R_301_5991@space_name
group by t.@R_301_5991@space_name;
2、查看表空间物理文件的名称及大小
select @R_301_5991@space_name,file_ID,file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by @R_301_5991@space_name;
3、查看回滚段名称及大小
select segment_name,@R_301_5991@space_name,r.status,
(initial_extent/1024) InitialExtent,(next_extent/1024) NextExtent,
max_extents,v.curext CurExtent
From dba_rollback_segs r,v$rollstat v
Where r.segment_ID = v.usn(+)
order by segment_name;
4、查看控制文件
select name from v$controlfile;
5、查看日志文件
select member from v$logfile;
6、查看表空间的使用情况
select sum(bytes)/(1024*1024) as free_space,@R_301_5991@space_name
from dba_free_space
group by @R_301_5991@space_name;
SELECT A.@R_301_5991@SPACE_name,A.BYTES TOTAL,B.BYTES USED,C.BYTES FREE,
(B.BYTES*100)/A.BYTES "% USED",(C.BYTES*100)/A.BYTES "% FREE"
FROM SYS.SM$TS_AVAIL A,SYS.SM$TS_USED B,SYS.SM$TS_FREE C
WHERE A.@R_301_5991@SPACE_name=B.@R_301_5991@SPACE_name AND A.@R_301_5991@SPACE_name=C.@R_301_5991@SPACE_name;
7、查看数据库库对象
select owner,object_type,status,count(*) count# from all_objects group by owner,status;
8、查看数据库的版本
Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';
查看数据库的创建日期和归档方式
Select Created,Log_Mode,Log_Mode From V$Database;
捕捉运行很久的sql
column username format a12
column opname format a16
column progress format a8
select username,sID,opname,
round(sofar*100 / totalwork,0) || '%' as progress,
time_remaining,sql_text
from v$session_longops,v$sql
where time_remaining <> 0
and sql_address = address
and sql_hash_value = hash_value
查看数据表的参数信息
SELECT partition_name,high_value,high_value_length,
pct_free,pct_used,ini_trans,max_trans,initial_extent,
next_extent,min_extent,max_extent,pct_increase,FREEListS,
freeList_groups,LOGGING,BUFFER_POol,num_rows,blocks,
empty_blocks,avg_space,chain_cnt,avg_row_len,sample_size,
last_analyzed
FROM dba_tab_partitions
--WHERE @R_301_5991@_name = :tname AND @R_301_5991@_owner = :towner
ORDER BY partition_position
查看还没提交的事务
select * from v$locked_object;
select * from v$transaction;
查找object为哪些进程所用
select
p.spID,
s.sID,
s.serial# serial_num,
s.username user_name,
a.type object_type,
s.osuser os_user_name,
a.owner,
a.object object_name,
decode(sign(48 - command),
1,
to_char(command),'Action Code #' || to_char(command) ) action,
p.program oracle_process,
s.terminal terminal,
s.program program,
s.status session_status
from v$session s,v$access a,v$process p
where s.paddr = p.addr and
s.type = 'USER' and
a.sID = s.sID and
a.object='SUBSCRIBER_ATTR'
order by s.username,s.osuser
回滚段查看
select rownum,sys.dba_rollback_segs.segment_name name,v$rollstat.extents
Extents,v$rollstat.RSSize Size_in_Bytes,v$rollstat.xacts XActs,
v$rollstat.gets Gets,v$rollstat.waits Waits,v$rollstat.writes Writes,
sys.dba_rollback_segs.status status from v$rollstat,sys.dba_rollback_segs,
v$rollname where v$rollname.name(+) = sys.dba_rollback_segs.segment_name and
v$rollstat.usn (+) = v$rollname.usn order by rownum
耗资源的进程（top session）
select s.schemaname schema_name,decode(sign(48 - command),status
session_status,s.osuser os_user_name,s.sID,p.spID,s.serial# serial_num,
nvl(s.username,'[Oracle process]') user_name,s.terminal terminal,st.value criteria_value from v$sesstat st,v$session s,v$process p
where st.sID = s.sID and st.statistic# = to_number('38') and ('ALL' = 'ALL'
or s.status = 'ALL') and p.addr = s.paddr order by st.value desc,p.spID asc,s.username asc,s.osuser asc
查看锁（lock）情况
select /*+ RulE */ ls.osuser os_user_name,ls.username user_name,
decode(ls.type,'RW','Row wait enqueue lock','TM','DML enqueue lock','TX',
'Transaction enqueue lock','ul','User supplIEd lock') lock_type,
o.object_name object,decode(ls.lmode,null,2,'Row Share',3,
'Row Exclusive',4,'Share',5,'Share Row Exclusive',6,'Exclusive',null)
lock_mode,o.owner,ls.sID,ls.serial# serial_num,ls.ID1,ls.ID2
from sys.dba_objects o,( select s.osuser,s.username,l.type,
l.lmode,s.serial#,l.ID1,l.ID2 from v$session s,
v$lock l where s.sID = l.sID ) ls where o.object_ID = ls.ID1 and o.owner
<> 'SYS' order by o.owner,o.object_name
查看等待（wait）情况
SELECT v$waitstat.class,v$waitstat.count count,SUM(v$sysstat.value) sum_value
FROM v$waitstat,v$sysstat WHERE v$sysstat.name IN ('db block gets',
'consistent gets') group by v$waitstat.class,v$waitstat.count
查看sga情况
SELECT name,BYTES FROM SYS.V_$SGASTAT ORDER BY name ASC
19。查看catched object
SELECT owner,name,db_link,namespace,
type,sharable_mem,loads,executions,
locks,pins,kept FROM v$db_object_cache
查看V$sqlAREA
SELECT sql_TEXT,SHaraBLE_MEM,PERSISTENT_MEM,RUNTIME_MEM,SORTS,
VERSION_COUNT,LOADED_VERSIONS,OPEN_VERSIONS,USERS_opening,EXECUTIONS,
USERS_EXECUTING,LOADS,FirsT_LOAD_TIME,INVALIDATIONS,PARSE_CALLS,disK_READS,
BUFFER_GETS,ROWS_PROCESSED FROM V$sqlAREA
查看object分类数量
select decode (o.type#,'INDEX','@R_301_5991@','CLUSTER','VIEW',
'SYNONYM','SEQUENCE','OTHER' ) object_type,count(*) quantity from
sys.obj$ o where o.type# > 1 group by decode (o.type#,3
,'SYNONYM','OTHER' ) union select
'ColUMN',count(*) from sys.col$ union select 'DB link',count(*) from
22。按用户查看object种类
select u.name schema,sum(decode(o.type#,NulL)) indexes,
sum(decode(o.type#,NulL)) @R_301_5991@s,NulL))
clusters,NulL)) vIEws,
NulL)) synonyms,NulL)) sequences,NulL,1))
others from sys.obj$ o,sys.user$ u where o.type# >= 1 and u.user# =
o.owner# and u.name <> 'PUBliC' group by u.name order by
sys.link$ union select 'CONSTRAINT',count(*) from sys.con$
有关connection的相关信息
1）查看有哪些用户连接
select s.osuser os_user_name,to_char(command),
'Action Code #' || to_char(command) ) action,p.program oracle_process,
status session_status,s.program program,s.fixed_@R_301_5991@_sequence activity_meter,'' query,
0 memory,0 max_memory,0 cpu_usage,s.serial# serial_num
from v$session s,v$process p where s.paddr=p.addr and s.type = 'USER'
order by s.username,s.osuser
2）根据v.sID查看对应连接的资源占用等情况
select n.name,
v.value,
n.class,
n.statistic#
from v$statname n,
v$sesstat v
where v.sID = 71 and
v.statistic# = n.statistic#
order by n.class,n.statistic#
3）根据sID查看对应连接正在运行的sql
select /*+ PUSH_SUBQ */
command_type,
sql_text,
sharable_mem,
persistent_mem,
runtime_mem,
sorts,
version_count,
loaded_versions,
open_versions,
users_opening,
executions,
users_executing,
loads,
first_load_time,
invalIDations,
parse_calls,
disk_reads,
buffer_gets,
rows_processed,
sysdate start_time,
sysdate finish_time,
'>' || address sql_address,
'N' status
from v$sqlarea
where address = (select sql_address from v$session where sID = 71)
4）根据v.sID查看对应连接的资源占用等情况
select n.name,n.statistic#
5）根据sID查看对应连接正在运行的sql
select /*+ PUSH_SUBQ */
command_type,
'N' status
from v$sqlarea
where address = (select sql_address from v$session where sID = 71)
查询表空间使用情况
select a.@R_301_5991@space_name "表空间名称",
100-round((nvl(b.bytes_free,0)/a.bytes_alloc)*100,2) "占用率(%)",
round(a.bytes_alloc/1024/1024,2) "容量(M)",
round(nvl(b.bytes_free,0)/1024/1024,2) "空闲(M)",
round((a.bytes_alloc-nvl(b.bytes_free,0))/1024/1024,2) "使用(M)",
Largest "最大扩展段(M)",
to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') "采样时间"
from (select f.@R_301_5991@space_name,
sum(f.bytes) bytes_alloc,
sum(decode(f.autoextensible,'YES',f.maxbytes,'NO',f.bytes)) maxbytes
from dba_data_files f
group by @R_301_5991@space_name) a,
(select f.@R_301_5991@space_name,
sum(f.bytes) bytes_free
from dba_free_space f
group by @R_301_5991@space_name) b,
(select round(max(ff.length)*16/1024,2) Largest,
ts.name @R_301_5991@space_name
from sys.fet$ ff,sys.file$ tf,sys.ts$ ts
where ts.ts#=ff.ts# and ff.file#=tf.relfile# and ts.ts#=tf.ts#
group by ts.name,tf.blocks) c
where a.@R_301_5991@space_name = b.@R_301_5991@space_name and a.@R_301_5991@space_name = c.@R_301_5991@space_name
查询表空间的碎片程度
select @R_301_5991@space_name,count(@R_301_5991@space_name) from dba_free_space group by @R_301_5991@space_name
having count(@R_301_5991@space_name)>10;
alter @R_301_5991@space name coalesce;
alter @R_301_5991@ name deallocate unused;
create or replace vIEw ts_blocks_v as
select @R_301_5991@space_name,block_ID,bytes,'free space' segment_name from dba_free_space
union all
select @R_301_5991@space_name,segment_name from dba_extents;
select * from ts_blocks_v;
select @R_301_5991@space_name,sum(bytes),max(bytes),count(block_ID) from dba_free_space
group by @R_301_5991@space_name;
查询有哪些数据库实例在运行
select inst_name from v$active_instances;
//取得服务器的IP 地址
select utl_inaddr.get_host_address from dual
//取得客户端的IP地址
select sys_context('userenv','host'),sys_context('userenv','ip_address') from dual
转载：http://blog.csdn.net/l106439814/article/details/7777727#comments
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