常用SQL查询

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)

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;