1 Oracle常用数据字典表
1、 查看当前用户的缺省表空间
SQL>select username,default_tablespace from user_users;
2、 查看当前用户的角色
SQL>select * from user_role_privs;
3、 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;
4、 查看用户下所有的表
SQL>select * from user_tables;
5、 查看用户下所有的表的列属性
SQL>select * from USER_TAB_COLUMNS where table_name=:table_Name;
6、 显示用户信息(所属表空间)
select default_tablespace, temporary_tablespace
from dba_users
where username = 'GAME';
7、 显示当前会话所具有的权限
SQL>select * from session_privs;
8、 显示指定用户所具有的系统权限
SQL>select * from dba_sys_privs where grantee='GAME';
9、 显示特权用户
select * from v$pwfile_users;
10、 显示用户信息(所属表空间)
select default_tablespace,temporary_tablespace
from dba_users where username='GAME';
11、 显示用户的PROFILE
select profile from dba_users where username='GAME';
2 表
1、 查看用户下所有的表
SQL>select * from user_tables;
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('&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的内存区里的表
SQL>select table_name,cache from user_tables where instr(cache,'Y')>0;
3 索引
1、 查看索引个数和类别
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 序列号
1、 查看序列号，last_number是当前值
SQL>select * from user_sequences;
5 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');
6 同义词
1、 查看同义词的名称
SQL>select * from user_synonyms;
7 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 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,status from 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');
9 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_tables: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
10 常用的动态性能视图：
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$waitstat：出现一个以上会话访问数据库的数据时的详细情况。当有一个以上的会话访问同一信息时，可出现等待情况。
总结了一下这些，彻底区别了视图与数据字典，也不那么容易混淆。嘿嘿!!!
11 常用SQL查询：
1、查看表空间的名称及大小
select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size
from dba_tablespaces t, dba_data_files d
where t.tablespace_name = d.tablespace_name
group by t.tablespace_name;
2、查看表空间物理文件的名称及大小
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by tablespace_name;
3、查看回滚段名称及大小
select segment_name, tablespace_name, r.status,
(initial_extent/1024) InitialExtent,(next_extent/1024) NextExtent,
max_extents, v.curext CurExtent
From dba_rollback_segs r, v$rollstat v
Where r.segment_id = v.usn(+)
order by segment_name;
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,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$TS_FREE C
WHERE A.TABLESPACE_NAME=B.TABLESPACE_NAME AND A.TABLESPACE_NAME=C.TABLESPACE_NAME;
7、查看数据库库对象
select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
8、查看数据库的版本
Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';
9、查看数据库的创建日期和归档方式
Select Created, Log_Mode, Log_Mode From V$Database;
10、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
11。查看数据表的参数信息
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.查看还没提交的事务
select * from v$locked_object;
select * from v$transaction;
13。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$process p
where s.paddr = p.addr and
s.type = 'USER' and
a.sid = s.sid and
a.object='SUBSCRIBER_ATTR'
order by s.username, s.osuser
14。回滚段查看
select rownum, sys.dba_rollback_segs.segment_name Name, v$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
15。耗资源的进程（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$process p
where st.sid = s.sid and st.statistic# = to_number('38') and ('ALL' = 'ALL'
or s.status = 'ALL') and p.addr = s.paddr order by st.value desc, p.spid asc, s.username asc, s.osuser asc
16。查看锁（lock）情况
select /*+ RULE */ ls.osuser os_user_name, ls.username user_name,
decode(ls.type, 'RW', 'Row wait enqueue lock', 'TM', 'DML enqueue lock', 'TX',
'Transaction enqueue lock', 'UL', 'User supplied lock') lock_type,
o.object_name object, decode(ls.lmode, 1, null, 2, 'Row Share', 3,
'Row Exclusive', 4, 'Share', 5, 'Share Row Exclusive', 6, 'Exclusive', null)
lock_mode, o.owner, ls.sid, ls.serial# serial_num, ls.id1, ls.id2
from sys.dba_objects o, ( select s.osuser, s.username, l.type,
l.lmode, s.sid, s.serial#, l.id1, l.id2 from v$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$waitstat.count
18。查看sga情况
SELECT NAME, BYTES FROM SYS.V_$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$db_object_cache
20。查看V$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$SQLAREA
21。查看object分类数量
select decode (o.type#,1,'INDEX' , 2,'TABLE' , 3 , 'CLUSTER' , 4, 'VIEW' , 5 ,
'SYNONYM' , 6 , 'SEQUENCE' , 'OTHER' ) object_type , count(*) quantity from
sys.obj$ o where o.type# > 1 group by decode (o.type#,1,'INDEX' , 2,'TABLE' , 3
, 'CLUSTER' , 4, 'VIEW' , 5 , 'SYNONYM' , 6 , 'SEQUENCE' , '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#, 1, 1, NULL)) indexes,
sum(decode(o.type#, 2, 1, NULL)) tables, sum(decode(o.type#, 3, 1, NULL))
clusters, sum(decode(o.type#, 4, 1, NULL)) views, sum(decode(o.type#, 5, 1,
NULL)) synonyms, sum(decode(o.type#, 6, 1, NULL)) sequences,
sum(decode(o.type#, 1, NULL, 2, NULL, 3, NULL, 4, NULL, 5, NULL, 6, 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$
23。有关connection的相关信息
1）查看有哪些用户连接
select s.osuser os_user_name, decode(sign(48 - command), 1, to_char(command),
'Action Code #' || to_char(command) ) action, p.program oracle_process,
status session_status, s.terminal terminal, s.program program,
s.username user_name, s.fixed_table_sequence activity_meter, '' query,
0 memory, 0 max_memory, 0 cpu_usage, s.sid, 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)
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)
24．查询表空间使用情况
select a.tablespace_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.tablespace_name,
sum(f.bytes) bytes_alloc,
sum(decode(f.autoextensible,'YES',f.maxbytes,'NO',f.bytes)) maxbytes
from dba_data_files f
group by tablespace_name) a,
(select f.tablespace_name,
sum(f.bytes) bytes_free
from dba_free_space f
group by tablespace_name) b,
(select round(max(ff.length)*16/1024,2) Largest,
ts.name tablespace_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.tablespace_name = b.tablespace_name and a.tablespace_name = c.tablespace_name
25. 查询表空间的碎片程度
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;
26。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