数据库手册：Oracle维护常用SQL语句二
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,s
