1 Oracle常用數據字典表
1、 查看當前用戶的缺省表空間
SQL>select username,default_tablespace from user_users;
2、 查看當前用戶的角色
SQL>select * from user_role_privs;
3、 查看當前用戶的系統權限和表級權限
SQL>select * from user_sys_privs;
SQL>select * from user_tab_privs;
4、 查看用戶下所有的表
SQL>select * from user_tables;
5、 查看用戶下所有的表的列屬性
SQL>select * from USER_TAB_COLUMNS where table_name=:table_Name;
6、 顯示用戶信息(所屬表空間)
select default_tablespace, temporary_tablespace
from dba_users www.2cto.com
where username = 'GAME';
7、 顯示當前會話所具有的權限
SQL>select * from session_privs;
8、 顯示指定用戶所具有的系統權限
SQL>select * from dba_sys_privs where grantee='GAME';
9、 顯示特權用戶
select * from v$pwfile_users;
10、 顯示用戶信息(所屬表空間)
select default_tablespace,temporary_tablespace
from dba_users where username='GAME';
11、 顯示用戶的PROFILE
select profile from dba_users where username='GAME';
2 表
1、 查看用戶下所有的表
SQL>select * from user_tables;
2、 查看名稱包含log字符的表
SQL>select object_name,object_id from user_objects
where instr(object_name,'LOG')>0;
3、 查看某表的創建時間
SQL>select object_name,created from user_objects where object_name=upper('&table_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('&table_name');
5、 查看放在Oracle的內存區裏的表
SQL>select table_name,cache from user_tables where instr(cache,'Y')>0;
3 索引
1、 查看索引個數和類別
SQL>select index_name,index_type,table_name from user_indexes order by table_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 序列號
1、 查看序列號，last_number是當前值
SQL>select * from user_sequences;
5 視圖
1、 查看視圖的名稱
SQL>select view_name from user_views;
2、 查看創建視圖的select語句
SQL>set view_name,text_length from user_views;
SQL>set long 2000; 說明：可以根據視圖的text_length值設定set long 的大小
SQL>select text from user_views where view_name=upper('&view_name');
6 同義詞
1、 查看同義詞的名稱
SQL>select * from user_synonyms;
7 約束條件 www.2cto.com
1、 查看某表的約束條件
SQL>select constraint_name, constraint_type,search_condition, r_constraint_name
from user_constraints where table_name = upper('&table_name');
SQL>select c.constraint_name,c.constraint_type,cc.column_name
from user_constraints c,user_cons_columns cc
where c.owner = upper('&table_owner') and c.table_name = upper('&table_name')
and c.owner = cc.owner and c.constraint_name = cc.constraint_name
order by cc.position;
8 存儲函數和過程
1、 查看函數和過程的狀態
SQL>select object_name,status from user_objects where object_type='FUNCTION';
SQL>select object_name,status from user_objects where object_type='PROCEDURE';
2、 查看函數和過程的源代碼
SQL>select text from all_source where owner=user and name=upper('&plsql_name');
9 常用的數據字典：
dba_data_files:通常用來查詢關於數據庫文件的信息
dba_db_links:包括數據庫中的所有數據庫鏈路，也就是databaselinks。
dba_extents:數據庫中所有分區的信息
dba_free_space:所有表空間中的自由分區
dba_indexs:關於數據庫中所有索引的描述
dba_ind_columns:在所有表及聚集上壓縮索引的列
dba_objects:數據庫中所有的對象
dba_rollback_segs:回滾段的描述
dba_segments:所有數據庫段分段的存儲空間
dba_synonyms:關於同義詞的信息查詢
dba_tables:數據庫中所有數據表的描述
dba_tabespaces:關於表空間的信息
dba_tab_columns:所有表描述、視圖以及聚集的列
dba_tab_grants/privs:對象所授予的權限
dba_ts_quotas:所有用戶表空間限額
dba_users:關於數據的所有用戶的信息
dba_views:數據庫中所有視圖的文本
10 常用的動態性能視圖：
v$datafile：數據庫使用的數據文件信息
v$librarycache：***享池中SQL語句的管理信息
v$lock：通過訪問數據庫會話，設置對象鎖的所有信息
v$log：從控制文件中提取有關重做日誌組的信息
v$logfile有關實例重置日誌組文件名及其位置的信息
v$parameter：初始化參數文件中所有項的值
v$process：當前進程的信息 www.2cto.com
v$rollname：回滾段信息
v$rollstat：聯機回滾段統計信息
v$rowcache：內存中數據字典活動/性能信息
v$session:有關會話的信息
v$sesstat：在v$session中報告當前會話的統計信息
v$sqlarea：***享池中使用當前光標的統計信息，光標是壹塊內存區域，有Oracle處理SQL語句時打開。
v$statname：在v$sesstat中報告各個統計的含義
v$sysstat：基於當前操作會話進行的系統統計
v$waitstat：出現壹個以上會話訪問數據庫的數據時的詳細情況。當有壹個以上的會話訪問同壹信息時，可出現等待情況。
總結了壹下這些，徹底區別了視圖與數據字典，也不那麽容易混淆。嘿嘿!!!
11 常用SQL查詢：
1、查看表空間的名稱及大小
select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size
from dba_tablespaces t, dba_data_files d
where t.tablespace_name = d.tablespace_name
group by t.tablespace_name;
2、查看表空間物理文件的名稱及大小
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by tablespace_name;
3、查看回滾段名稱及大小
select segment_name, tablespace_name, r.status,
(initial_extent/1024) InitialExtent,(next_extent/1024) NextExtent,
max_extents, v.curext CurExtent
From dba_rollback_segs r, v$rollstat v
Where r.segment_id = v.usn(+)
order by segment_name;
www.2cto.com
4、查看控制文件
select name from v$controlfile;
5、查看日誌文件
select member from v$logfile;
6、查看表空間的使用情況
select sum(bytes)/(1024*1024) as free_space,tablespace_name
from dba_free_space
group by tablespace_name;
SELECT A.TABLESPACE_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$TS_FREE C
WHERE A.TABLESPACE_NAME=B.TABLESPACE_NAME AND A.TABLESPACE_NAME=C.TABLESPACE_NAME;
7、查看數據庫庫對象
select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
8、查看數據庫的版本
Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';
9、查看數據庫的創建日期和歸檔方式
Select Created, Log_Mode, Log_Mode From V$Database;
10、捕捉運行很久的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
11。查看數據表的參數信息
SELECT partition_name, high_value, high_value_length, tablespace_name,
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 table_name = :tname AND table_owner = :towner
ORDER BY partition_position
12.查看還沒提交的事務
select * from v$locked_object;
select * from v$transaction;
13。查找object為哪些進程所用
select www.2cto.com
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$process p
where s.paddr = p.addr and
s.type = 'USER' and
a.sid = s.sid and
a.object='SUBSCRIBER_ATTR'
order by s.username, s.osuser
14。回滾段查看
select rownum, sys.dba_rollback_segs.segment_name Name, v$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
15。耗資源的進程（top session）
select s.schemaname schema_name, decode(sign(48 - command), 1,
to_char(command), 'Action Code #' || to_char(command) ) action, 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,
s.program program, st.value criteria_value from v$sesstat st, v$session s , v$process p
where st.sid = s.sid and st.statistic# = to_number('38') and ('ALL' = 'ALL'
or s.status = 'ALL') and p.addr = s.paddr order by st.value desc, p.spid asc, s.username asc, s.osuser asc www.2cto.com
16。查看鎖（lock）情況
select /*+ RULE */ ls.osuser os_user_name, ls.username user_name,
decode(ls.type, 'RW', 'Row wait enqueue lock', 'TM', 'DML enqueue lock', 'TX',
'Transaction enqueue lock', 'UL', 'User supplied lock') lock_type,
o.object_name object, decode(ls.lmode, 1, null, 2, 'Row Share', 3,
'Row Exclusive', 4, 'Share', 5, 'Share Row Exclusive', 6, 'Exclusive', null)
lock_mode, o.owner, ls.sid, ls.serial# serial_num, ls.id1, ls.id2
from sys.dba_objects o, ( select s.osuser, s.username, l.type,
l.lmode, s.sid, s.serial#, l.id1, l.id2 from v$session s,
v$lock l where s.sid = l.sid ) ls where o.object_id = ls.id1 and o.owner
<> 'SYS' order by o.owner, o.object_name
17。查看等待（wait）情況
SELECT v$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$waitstat.count
18。查看sga情況
SELECT NAME, BYTES FROM SYS.V_$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$db_object_cache
20。查看V$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