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;

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

SELECTpartition_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

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.sidand

a.object='SUBSCRIBER_ATTR'

order by s.username, s.osuser

14?；貪L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 andst.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.id2from v$session s,

v$lock lwhere 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$db_object_cache20。查看V$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分類數量

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。按用戶查看object種類

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))

othersfrom sys.obj$ o, sys.user$ uwhere o.type# >= 1 and;u.user# =

o.owner# andu.name <> 'PUBLIC'group by u.name;order by

sys.link$ union select 'CONSTRAINT' , count(*) from sys.con$

23。有關connection的相關信息

1）查看有哪些用戶連接

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 pwhere s.paddr=p.addr and;s.type = 'USER'

order by s.username, s.osuser

2）根據v.sid查看對應連接的資源占用等情況

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）根據sid查看對應連接正在運行的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．查詢表空間使用情況

select a.tablespace_name "表空間名稱",

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) "空閑(M)",

round((a.bytes_alloc-nvl(b.bytes_free,0))/1024/1024,2) "使用(M)",

Largest "最大擴展段(M)",

to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') "采樣時間"

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. 查詢表空間的碎片程度

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。查詢有哪些數據庫實例在運行

select inst_name from v$active_instances;

===========================================================

######### 創建數據庫----look $ORACLE_HOME/rdbms/admin/buildall.sql #############

create database db01

maxlogfiles 10

maxdatafiles 1024

maxinstances 2

logfile

GROUP 1 ('/u01/oradata/db01/log_01_db01.rdo') SIZE 15M,

GROUP 2 ('/u01/oradata/db01/log_02_db01.rdo') SIZE 15M,

GROUP 3 ('/u01/oradata/db01/log_03_db01.rdo') SIZE 15M,

datafile 'u01/oradata/db01/system_01_db01.dbf') SIZE 100M,

undo tablespace UNDO

datafile '/u01/oradata/db01/undo_01_db01.dbf' SIZE 40M