database 概况信息检查
# 检查 database 基本信息
select * from v$version;
select name ,open_mode,log_mode from v$database;
select instance_number,instance_name ,status from gv$instance;
show parameter cpu_count
show parameter block_size
select group#,thread#,members,bytes/1024/1024 from gv$log;
show sga
select count(*) from v$controlfile
select count(*) from v$tempfile;
select count(*) from v$datafile;
查看数据文件信息
# 检查表空间数据文件信息
col tablespace_name for a30
select tablespace_name , sum(bytes)/1024/1024 from dba_temp_files group by tablespace_name;
# 检查表空间
SELECT
TABLESPACE_NAME,EXTENT_MANAGEMENT,ALLOCATION_TYPE,SEGMENT_SPACE
_MANAGEMENT FROM DBA_TABLESPACES;
# 检查数据文件状态
select count(*),status from v$datafile group by status;
# 检查表空间使用情况
select
f.tablespace_name,
a.total,
f.free,(a.total-f.free)/1024 "used SIZE(G)"
,round((f.free/a.total)*100) "% Free"
from
(select tablespace_name, sum(bytes/(1024*1024)) total from dba_data_files group by
tablespace_name) a,
(select tablespace_name, round(sum(bytes/(1024*1024))) free from dba_free_space
group by tablespace_name) f
WHERE a.tablespace_name = f.tablespace_name(+)
order by "% Free"
/
# 查询临时 segment 使用情况
COL username FORMAT a10;
COL segtype FORMAT a10;
SELECT username, segtype, extents "Extents Allocated"
,blocks "Blocks Allocated"
FROM v$tempseg_usage;
# 查看临时表空间大小
select tablespace_name,file_name,bytes/1024/1024 "file_size(M)",autoextensible from dba_temp_files;
select status,enabled, name, bytes/1024/1024 file_size from v$tempfile;
# 查看临时表空间的使用情况
SELECT temp_used.tablespace_name,
total - used as "Free",
total as "Total",
round(nvl(total - used, 0) * 100 / total, 3) "Free percent"
FROM (SELECT tablespace_name, SUM(bytes_used) / 1024 / 1024 used
FROM GV_$TEMP_SPACE_HEADER
GROUP BY tablespace_name) temp_used,
(SELECT tablespace_name, SUM(bytes) / 1024 / 1024 total
FROM dba_temp_files
GROUP BY tablespace_name) temp_total
WHERE temp_used.tablespace_name = temp_total.tablespace_name
# 查找消耗较多临时表空间的sql
Select se.username,
se.sid,
su.extents,
su.blocks * to_number(rtrim(p.value)) as Space,
tablespace,
segtype,
sql_text
from v$sort_usage su, v$parameter p, v$session se, v$sql s
where p.name = ‘db_block_size‘
and su.session_addr = se.saddr
and s.hash_value = su.sqlhash
and s.address = su.sqladdr
order by se.username, se.sid
# 查看当前临时表空间使用大小与正在占用临时表空间的sql语句
select sess.SID, segtype, blocks * 8 / 1000 "MB", sql_text
from v$sort_usage sort, v$session sess, v$sql sql
where sort.SESSION_ADDR = sess.SADDR
and sql.ADDRESS = sess.SQL_ADDRESS
order by blocks desc;
# 查看数据文件信息 , 若文件较多可以根据需要字段进行排序 输出 top 10
col datafile for a60
SELECT fs.phyrds "Reads", fs.phywrts "Writes"
,fs.avgiotim "Average I/O Time", df.name "Datafile"
FROM v$datafile df, v$filestat fs WHERE df.file# = fs.file#;
# 查看所有数据文件 i/ o 情况 , 若文件太多 , 可以改写 为 top 10 select *( order by xx desc) where
rownum<=10。其中phyrds为物理读的次数极为Reads，phywrts为物理写的次数极为Writes，phyblkrd为物理块 读的次数即为br，phyblkwrt为物理写的次数即为bw。readtime为耗费在物理读上的总时间极为RTime，writetim为耗费在物理 写上的总时间即为WTime。这两个值只有在参数timed_statistics参数为true时才有效。
COL ts FORMAT a10 HEADING "Tablespace";
COL reads FORMAT 999990;
COL writes FORMAT 999990;
COL br FORMAT 999990 HEADING "BlksRead";
COL bw FORMAT 999990 HEADING "BlksWrite";
COL rtime FORMAT 999990;
COL wtime FORMAT 999990;
SELECT ts.name AS ts, fs.phyrds "Reads", fs.phywrts "Writes"
,fs.phyblkrd AS br, fs.phyblkwrt AS bw
,fs.readtim "RTime", fs.writetim "WTime"
FROM v$tablespace ts, v$datafile df, v$filestat fs
WHERE ts.ts# = df.ts# AND df.file# = fs.file#
UNION
SELECT ts.name AS ts, ts.phyrds "Reads", ts.phywrts "Writes",ts.phyblkrd AS br, ts.phyblkwrt AS bw
,ts.readtim "RTime", ts.writetim "WTime"
FROM v$tablespace ts, v$tempfile tf, v$tempstat ts
WHERE ts.ts# = tf.ts# AND tf.file# = ts.file# ORDER BY 1;
# 获取 top 10 热 segment
set linesize 180
col object_name for a40
select * from
(select
ob.owner, ob.object_name, sum(b.tch) Touchs
from x$bh b , dba_objects ob
where b.obj = ob.data_object_id
and b.ts# > 0
group by ob.owner, ob.object_name
order by sum(tch) desc)
where rownum <=10
# 判断物理读最多的 object
select * from (select owner,object_name,value from v$segment_statistics where
statistic_name=‘physical reads‘ order by value desc) where rownum<=10
# 查看热点数据文件 ( 从单块读取时间判断 )
col FILE_NAME for a60
set linesize 180
SELECT t.file_name,
t.tablespace_name,
round(s.singleblkrdtim/s.singleblkrds, 2) AS CS,
s.READTIM,
s.WRITETIM
FROM v$filestat s, dba_data_files t
WHERE s.file# = t.file_id and s.singleblkrds <>0 and rownum<=10 order by cs desc
#估算表空间大小
select a.tablespace_name,
round(a.s,2) "CURRENT_TOTAL(MB)" ,
round((a.s - f.s),2) "USED(MB)" ,
f.s "FREE(MB)" ,
round(f.s / a.s * 100, 2) "FREE%" ,
g.autoextensible,
round(a.ms,2) "MAX_TOTAL(MB)"
from ( select d.tablespace_name,
sum (bytes / 1024 / 1024) s,
sum (decode(maxbytes, 0, bytes, maxbytes) / 1024 / 1024) ms
from dba_data_files d
group by d.tablespace_name) a,
( select f.tablespace_name, sum (f.bytes / 1024 / 1024) s
from dba_free_space f
group by f.tablespace_name) f,
( select distinct tablespace_name, autoextensible
from DBA_DATA_FILES
where autoextensible = ‘YES‘
union
select distinct tablespace_name, autoextensible
from DBA_DATA_FILES
where autoextensible = ‘NO‘
and tablespace_name not in
( select distinct tablespace_name
from DBA_DATA_FILES
where autoextensible = ‘YES‘ )) g
where a.tablespace_name = f.tablespace_name
and g.tablespace_name = f.tablespace_name order by "FREE%" ;
#精确计算表空间大小，消耗系统资源，慎用
SELECT F.TABLESPACE_NAME,
A.ALL_TOTAL "总空间" ,
A.ALL_USED "总使用空间" ,
A.ALL_TOTAL - A.ALL_USED "总剩余空间" ,
(A.ALL_TOTAL - A.ALL_USED) / A.ALL_TOTAL * 100 "总剩余比例" ,
A.TOTAL "当前大小" ,
U.USED "当前使用空间" ,
F. FREE "当前剩余空间" ,
(U.USED / A.TOTAL) * 100 "当前使用比例" ,
(F. FREE / A.TOTAL) * 100 "当前剩余比例"
FROM ( SELECT TABLESPACE_NAME,
SUM (BYTES / (1024 * 1024 * 1024)) TOTAL,
SUM (DECODE(AUTOEXTENSIBLE, ‘YES‘ , MAXBYTES, BYTES) /
(1024 * 1024 * 1024)) ALL_TOTAL,
SUM (USER_BYTES) / (1024 * 1024 * 1024) ALL_USED
FROM DBA_DATA_FILES
GROUP BY TABLESPACE_NAME) A,
( SELECT TABLESPACE_NAME, SUM (BYTES / (1024 * 1024 * 1024)) USED
FROM DBA_EXTENTS
GROUP BY TABLESPACE_NAME) U,
( SELECT TABLESPACE_NAME, SUM (BYTES / (1024 * 1024 * 1024)) FREE
FROM DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME) F
WHERE A.TABLESPACE_NAME = F.TABLESPACE_NAME(+)
AND A.TABLESPACE_NAME = U.TABLESPACE_NAME(+)
ORDER BY (A.ALL_TOTAL - A.ALL_USED) / A.ALL_TOTAL,F. FREE / A.TOTAL ASC ;
查看redo
# 检查日志切换频率
select sequence#,to_char(first_time,‘yyyymmdd_hh24:mi:ss‘)
firsttime,round((first_time-lag(first_time) over(order by first_time))*24*60,2) minutes from
v$log_history where first_time > sysdate - 1 order by first_time ,minutes;
# 检查 lgwr i/o 性能 (time_waited/total_waits:表示平均lgwr写入完成时间若>1表示写入过慢 )
select total_waits,time_waited,average_wait,time_waited/total_waits as avg from
v$system_event where event = ‘log file parallel write‘;
# 查询 redo block size
select max(lebsz) from x$kccle;
# 查看 user commit 次数
select to_number(value,99999999999) from v$sysstat where name=‘user commits‘;
# 查看系统运行时间
select (sysdate - startup_time)*24*60*60 as seconds from v$instance
# 计算出每秒用户提交次数
select user_commit 次数 / 系统运行时间 from dual;
# 计算出每个事务平均处理多少个 redo block
select value from v$sysstat where name = ‘redo blocks written‘;
select a.redoblocks/b.trancount from (select value redoblocks from v$sysstat where name=‘redo
blocks written‘) a ,(select value trancount from v$sysstat where name=‘user commits‘) b
# 计算每天产生了多少日志
SELECT TO_CHAR (TRUNC (COMPLETION_TIME), ‘yyyy-mm-dd‘) "日期",
SUM (blocks * BLOCK_SIZE) / 1024 / 1024 / 1024 "日志量(G)"
FROM V$ARCHIVED_LOG
WHERE dest_id = 1
GROUP BY TRUNC (COMPLETION_TIME)
ORDER BY TRUNC (COMPLETION_TIME) DESC;
sga,pga, 命中率
# sga,pga, 命中率
# 检查 sga
show sga
select * from v$sga;
# 查看buffer cache设置建议
select size_for_estimate, estd_physical_read_factor,
to_char(estd_physical_reads,99999999999999999999999) as"estd_physical_reads" from
v$db_cache_advice where name = ‘DEFAULT‘;
COL pool FORMAT a10;
SELECT (SELECT ROUND(value/1024/1024,0) FROM v$parameter
WHERE name = ‘db_cache_size‘) "Current Cache(Mb)"
,name "Pool", size_for_estimate "Projected Cache(Mb)"
,ROUND(100-estd_physical_read_factor,0) "Cache Hit Ratio%"
FROM v$db_cache_advice
WHERE block_size = (SELECT value FROM v$parameter
WHERE name = ‘db_block_size‘)
ORDER BY 3;
# 查看 cache 池
show parameter cache
# 查看 buffer cache 中 defalut pool 命中率
select name,1-(physical_reads)/(consistent_gets+db_block_gets)
from v$buffer_pool_statistics;
# 检查 shared pool
show parameter shared
# 检查 shared pool 中 library cache
select namespace,pinhitratio from v$librarycache;
# 检查整体命中率 (library cache)
select sum(pinhits)/sum(pins) from v$librarycache;
select sum(pins) "hits",
sum(reloads) "misses",
sum(pins)/(sum(pins)+sum(reloads)) "Hits Ratio"
from v$librarycache;
# 检查 shared pool free space
SELECT * FROM V$SGASTAT
WHERE NAME = ‘free memory‘
AND POOL = ‘shared pool‘;
# 每个子shared pool 由单独的 shared pool latch保护，查看他们的命中率 shared pool latch，用于shared pool空间回收分配使用的latch
col name format a15
select addr,name,gets,misses,1-misses/gets from v$latch_children where name=‘shared pool‘;
# 使用 v$shared_pool_advice 计算不同 shared pool 大小情况下，响应时间， S 单位
SELECT ‘Shared Pool‘ component,
shared_pool_size_for_estimate estd_sp_size,
estd_lc_time_saved_factor parse_time_factor,
CASE
WHEN current_parse_time_elapsed_s + adjustment_s < 0 THEN
0
ELSE
current_parse_time_elapsed_s + adjustment_s
END response_time
FROM (SELECT shared_pool_size_for_estimate,
shared_pool_size_factor,
estd_lc_time_saved_factor,
a.estd_lc_time_saved,
e.VALUE / 100 current_parse_time_elapsed_s,
c.estd_lc_time_saved - a.estd_lc_time_saved adjustment_s FROM v$shared_pool_advice a,
(SELECT * FROM v$sysstat WHERE NAME = ‘parse time elapsed‘) e,
(SELECT estd_lc_time_saved FROM v$shared_pool_advice
WHERE shared_pool_size_factor = 1) c)
/
# 查看 shared pool 中 各种类型的 chunk 的大小数量
SELECT KSMCHCLS CLASS, COUNT(KSMCHCLS) NUM, SUM(KSMCHSIZ) SIZ,
To_char( ((SUM(KSMCHSIZ)/COUNT(KSMCHCLS)/1024)),‘999,999.00‘)||‘k‘ "AVG
SIzE"
FROM X$KSMSP GROUP BY KSMCHCLS;
# 查看是否有库缓冲有关的等待事件
select sid,seq#,event,p1,p1raw,p2,p2raw,p3,p3raw,state from v$session_wait where event like
‘library%‘;
# 查询 sga 中各个 pool 情况
COL name FORMAT a32;
SELECT pool, name, bytes FROM v$sgastat
WHERE pool IS NULL
OR pool != ‘shared pool‘ OR (pool = ‘shared pool‘
AND (name IN(‘dictionary cache‘,‘enqueue‘,‘library
cache‘,‘parameters‘,
‘processes‘,‘sessions‘,‘free memory‘)))
ORDER BY pool DESC NULLS FIRST, name;
SELECT * FROM V$SGAINFO;
# 查看使用 shard_pool 保留池情况
SELECT request_misses, request_failures, free_space
FROM v$shared_pool_reserved;
Oracle 专门从共享池内置出一块区域来来分配内存保持这些大块。这个保留共享池的默认大小是共享池的5%(_shared_pool_reserved_pct 5 控制 ) oracle 建设置为 10% 。大小通过参数 SHARED_POOL_RESERVED_SIZE 改。它是从共享池中分配，不是直接从 SGA 中分配的，它是共享池的保留部分，专门用于存储大块段#shared pool 中内存大于 _SHARED_POOL_RESERVED_MIN_ALLOC 将放入 shared pool 保留池 , 保留池维护一个单独的 freelist,lru ，并且不会在 lru 列表存recreatable 类型 chunks ，普通 shared pool 的释放与 shared pool 保留池无关。
# 关于设置 SHARED_POOL_RESERVED_SIZE
#1.如果系统出现ora-04031, 发现请求内存都是大于 _SHARED_POOL_RESERVED_MIN_ALLOC (default 10GR2 4400) , 且v$shared_pool_reserved 中有大量 REQUEST_MISSES( 并且可以看下LAST_MISS_SIZE )表示 SHARED_POOL_RESERVED_SIZE 太小了需要大的内存的请求失败 , 那么需要加大SHARED_POOL_RESERVED_SIZE
#2. 如果 ora-04031 请求内存出现在 4100-4400 并造成 shared pool lru 合并 , 老化换出内存 , 可以调小 _SHARED_POOL_RESERVED_MIN_ALLOC 让此部分内存进入shared reserved pool, 相应的加大SHARED_POOL_RESERVED_SIZE
#3. 从 v$shared_pool_reserved 来判断 , 如果 REQUEST_FAILURES>0( 出现过 ora-04031) 且LAST_FAILURE_SIZE( 最后请求内存大小 )>_SHARED_POOL_RESERVED_MIN_ALLOC表示 shared reserved pool 缺少连续内存 , 可以加大 SHARED_POOL_RESERVED_SIZE, 减少 _SHARED_POOL_RESERVED_MIN_ALLOC 少放对象 , 并相对加大 shared_pool_size
# 要是反过来 REQUEST_FAILURES>0( 出现过 ora-04031) 且 LAST_FAILURE_SIZE( 最后请求内存大小)<_SHARED_POOL_RESERVED_MIN_ALLOC, 表示 在 shared pool 中缺少连续内存 , 可以加减少_SHARED_POOL_RESERVED_MIN_ALLOC 多放入一些对象 , 减少 sharedpool 压力 , 适当加大shared_pool_size,SHARED_POOL_RESERVED_SIZE
# 查询还保留在 library cache 中，解析次数和执行次数最多的 sql( 解析 * 执行 )
COL sql_text FORMAT A38;
SELECT * FROM(
SELECT parse_calls*executions "Product", parse_calls
"Parses"
,executions "Execs", sql_text FROM v$sqlarea ORDER BY 1 DESC)
WHERE ROWNUM <= 10;
# 查看 pga
show parameters area_size
SELECT * FROM v$pgastat;
# 查看pga建议
SELECT (SELECT ROUND(value/1024/1024,0) FROM v$parameter
WHERE name = ‘pga_aggregate_target‘) "Current Mb"
, ROUND(pga_target_for_estimate/1024/1024,0) "Projected Mb"
, ROUND(estd_pga_cache_hit_percentage) "%"
FROM v$pga_target_advice
ORDER BY 2;
# 查看数据库 cache 或 keep 了哪些 object
COL table_name FORMAT A16
COL index_name FORMAT A16
SELECT table_name AS "Table", NULL, buffer_pool, cache FROM
user_tables
WHERE buffer_pool != ‘DEFAULT‘ OR TRIM(cache)=‘Y‘
UNION
SELECT table_name, index_name, NULL, buffer_pool FROM
user_indexes
WHERE buffer_pool != ‘DEFAULT‘
ORDER BY 1, 2 NULLS FIRST;
# 取消 cache 或 keep(keep pool)
ALTER TABLE XX NOCACHE;
SELECT ‘ALTER INDEX ‘||index_name||‘ STORAGE(BUFFER_POOL DEFAULT);‘
FROM USER_INDEXES WHERE BUFFER_POOL!=‘DEFAULT‘;
检查undo
show parameter undo_
# 检查 undo rollback segment 使用情况
select name ,rssize,extents,latch,xacts,writes,gets,waits from v$rollstat a,v$rollname b where
a.usn=b.usn order by waits desc;
select a.redoblocks/b.trancount from (select value redoblocks from v$sysstat where name=‘redo
blocks written‘) a ,(select value trancount from v$sysstat where name=‘user commits‘) b;
# 计算每秒钟产生的 undoblk 数量
select sum(undoblks)/sum((end_time-begin_time)*24*60*60) from v$undostat;
#Undospace=UR*UPS*blocksize + overload(10%), 计算 undo tablespace 大小
show parameter block_size
show parameter undo_retention
# 计算undo表空间大小
#select undo_retention* 每 秒 产 生 undoblk 数 量 *block_size/1024/1024/1024+
(1+1undo_retention* 每秒产生 undoblk 数量 *block_size/1024/1024/1024*0.1) from dual;
# 查询 undo 具体信息
COL undob FORMAT 99990;
COL trans FORMAT 99990;
COL snapshot2old FORMAT 9999999990;
SELECT undoblks "UndoB", txncount "Trans"
,maxquerylen "LongestQuery", maxconcurrency "MaxConcurrency"
,ssolderrcnt "Snapshot2Old", nospaceerrcnt "FreeSpaceWait"
FROM v$undostat;
# 在内存中排序比率 ( 最优排序 )
SELECT ‘Sorts in Memory ‘ "Ratio"
, ROUND(
(SELECT SUM(value) FROM V$SYSSTAT WHERE name = ‘sorts (memory)‘)
/ (SELECT SUM(value) FROM V$SYSSTAT
WHERE name IN (‘sorts (memory)‘, ‘sorts (disk)‘)) * 100, 5)
||‘%‘ "Percentage"
FROM DUAL;
# 查看当前系统undo使用情况
SELECT DISTINCT STATUS "状态",
COUNT(*) "EXTENT数量",
SUM(BYTES) / 1024 / 1024 / 1024 "UNDO大小"
FROM DBA_UNDO_EXTENTS
GROUP BY STATUS;
# 查看当前系统和undo相关的会话
SELECT r.NAME 回滚段名,s.sid SID,s.serial# Serial,
s.username 用户名,s.machine 机器名,
t.start_time 开始时间,t.status 状态,
t.used_ublk 撤消块,USED_UREC 撤消记录,
t.cr_get 一致性取,t.cr_change 一致性变化,
t.log_io "逻辑I/O",t.phy_io "物理I/O",
t.noundo NoUndo,g.extents Extents,substr(s.program, 1, 50) 操作程序
FROM v$session s, v$transaction t, v$rollname r,v$rollstat g
WHERE t.addr = s.taddr
AND t.xidusn = r.usn
AND r.usn = g.usn
ORDER BY t.used_ublk desc;
查看对象
# 检查数据库中无效对象
SELECT owner, object_type,count(object_name) FROM dba_objects WHERE status= ‘INVALID‘group by owner,object_type;
# 检查是否有禁用约束
SELECT owner, constraint_name, table_name, constraint_type, status
FROM dba_constraints
WHERE status =‘DISABLE‘ and constraint_type=‘P‘
# 检查是否有禁用 trigger
col owner for a10
col taigger_name for a10
cok table_name for a30
col table_name for a30
SELECT owner, trigger_name, table_name, status FROM dba_triggers WHERE status =
‘DISABLED‘;
# 在某个表下找的索引情况
col column_name for a12
set linesize 180
select user_indexes.table_name, user_indexes.index_name,uniqueness, column_name
from user_ind_columns, user_indexes
where user_ind_columns.index_name = user_indexes.index_name
and user_ind_columns.table_name = user_indexes.table_name
AND user_indexes.table_name=‘&tb_name‘
order by user_indexes.table_type, user_indexes.table_name,
user_indexes.index_name, column_position;
# 检查与索引相关的字段
select * from user_ind_columns where index_name=upper(‘&index_name‘);
# 检查索引的唯一性的
col uniq format a10 heading ‘Uniqueness‘ justify c trunc
col indname format a40 heading ‘Index Name‘ justify c trunc
col colname format a25 heading ‘Column Name‘ justify c trunc
break -
on indname skip 1 -
on uniq
select
ind.uniqueness uniq,
ind.owner||‘.‘||col.index_name indname,
col.column_name colname
from
dba_ind_columns col,
dba_indexes ind
where
ind.owner = upper(‘&ixowner‘)
and
ind.table_name = upper(‘&tabname‘)
and
col.index_owner = ind.owner
and
col.index_name = ind.index_name
order by
col.index_name,
col.column_position
查看当前系统状态
# 检查系统中排行前10的等待事件
col event for a30
包括空闲等待事件
select * from (select sid,event,p1,p2,p3,p1text,WAIT_TIME,SECONDS_IN_WAIT from v$session_wait where
event not like ‘SQL%‘ and event not like ‘rdbms%‘ order by wait_time desc) where rownum <=10;
不包括空闲等待事件
select * from (select sid,event,p1,p2,p3,p1text,WAIT_TIME,SECONDS_IN_WAIT,state from v$session_wait where wait_class# <> 6
order by wait_time desc) where rownum <=10;
# 查看经常被使用而没有pin在内存中的对象
# 形成生成pin住共享池中当前没有被pin住的对象的sql语句。在执行exec sys.DBMS_SHARED_POOL.keep(‘JXXXT.IN_GZ_LOGS‘,‘P‘);可能会报出未定义的错误，需要在sqlplus 下执行脚本$ORACLE_HOME/rdbms/admin/dbmspool.sql
select ‘exec sys.DBMS_SHARED_POOL.keep(‘||chr(39)||owner||‘.‘||NAME||chr(39)||‘,‘||chr(39)||‘P‘||chr(39)||‘);‘ as sql_to_run
from V$DB_OBJECT_CACHE where TYPE in (‘PACKAGE‘,‘FUNCTION‘,‘PROCEDURE‘) and loads > 50 and kept=‘NO‘ and executions > 50;
# 查看使用了超过10MB内存 而没有pin的对象
SELECT owner,name,sharable_mem,kept FROM V$DB_OBJECT_CACHE
WHERE sharable_mem > 102400 AND kept = ‘NO‘ ORDER BY sharable_mem DESC;
# 查看大的没有被pin住的对象.
set linesize 150
col sz for a10
col name for a100
col keeped for a6
select to_char(sharable_mem / 1024,‘999999‘) sz_in_K, decode(kept, ‘yes‘,‘yes ‘,‘‘) keeped,
owner||‘,‘||name||lpad(‘ ‘,29 - (length(owner) + length(name))) || ‘(‘ ||type||‘)‘name,
null extra, 0 iscur from v$db_object_cache v where sharable_mem > 1024*1000;
# 查看大的没有被pin住的过程，包和函数
col type for a25
col name for a40
col owner for a25
select owner,name,type,round(sum(sharable_mem/1024),1) sharable_mem_K from v$db_object_cache where kept = ‘NO‘
and (type = ‘PACKAGE‘ or type = ‘FUNCTION‘ or type = ‘PROCEDURE‘)
group by owner,name,type order by 4;
需要被pin入内存中的对象主要有：常用的较大的存储对象，如standard、diutil包；编译的常用的triggers；sequences。
最好在开机时就将其pin入内存中。这样，既是使用命令alter system flush shared_pool时，也不会讲这些object flush掉。具体pin对象到内存的方法使用DBMS_SHARED_POOL.keep存储过程。可以用unkeep方法解除其pin状态。
db_object_cache和碎片化
碎片化造成在共享池中虽然有许多小的碎片可以使用，但没有足够大的连续空间，这在共享池中是普遍的现象。消除共享池错误的关键就是即将加载对象的大小是否 可能会产生问题。一旦知道了这个存在问题的PL/SQL，那么就可以在数据库启动时(这时共享池是完全连续的)就将这个代码固定。这将确保在调用大型包 时，它已经在共享池里，而不是在共享池中搜索连续的碎片(在使用系统时，这些碎片可能就不复存在)。可以查询V$DB_OBJECT_CACHE视图来判 断PL/SQL是否很大并且还没有被标识为"kept"的标记。今后需要加载这些对象时，可能会产生问题(因为它们的大小和需要占用大量连续的内存)。通 过查询V$DB_OBJECT_CACHE表，可以发现那些没有固定，但由于所需空间太大而很有可能导致潜在问题的对象。
# 查询一下回滚段的使用情况，其中USED_UREC为undo记录的使用条目数，USED_UBLK为undo块的使用数目
set linesize 180
SELECT a.sid, a.username, b.xidusn, b.used_urec, b.used_ublk
from v$session a, v$transaction b
WHERE a.saddr = b.ses_addr;
# 查看锁住对象的会话信息，操作系统进程信息
set linesize 180
select object_name,machine,s.sid,s.serial#,p.spid
from v$locked_object l,dba_objects o ,v$session s,v$process p
where l.object_id=o.object_id and l.session_id=s.sid
and s.paddr=p.addr
# 根据进程查看sql
select sql_text
from v$sqltext_with_newlines
where (hash_value,address) in (select sql_hash_value,sql_address from v$session where sid=(select ses.sid from v$session ses,v$process pro
where pro.spid=&spid
and ses.paddr=pro.addr)) order by address,piece;
# 查看被锁的表的被锁时间
set linesize 180
select b.username,b.sid,b.serial#,logon_time
from v$locked_object a,v$session b
where a.session_id = b.sid order by b.logon_time;
# 查看被锁的对象和引起锁的sql
select a.sid,a.username,d.object_name, b.sql_text
from v$session a,v$sql b, v$locked_object c,dba_objects d
where a.sql_hashvalue=b.hash_value
and a.sid = c.session_id
and d.object_id = c.object_id;
# 查看锁定的会话信息
select b.username,b.sid,b.serial#,logon_time
from v$locked_object a,v$session b
where a.session_id = b.sid order by b.logon_time
# 杀死相关会话
alter system kill session ‘sid,serial#‘;
# 如果出现ora-00031错误，则
alter system kill session ‘sid,serial#‘ immediate；
# 亦可先查询该会话相对应的操作系统进程，在操作系统上进行kill
TOP SQL
# 逻辑读 TOP 10
select *
from (select sqt.logicr logical_Reads,
sqt.exec Executions,
decode(sqt.exec, 0, to_number(null), (sqt.logicr / sqt.exec)) Reads_per_Exec ,
(100 * sqt.logicr) /
(SELECT sum(e.VALUE) - sum(b.value)
FROM DBA_HIST_SYSSTAT b, DBA_HIST_SYSSTAT e
WHERE B.SNAP_ID =7634
AND E.SNAP_ID =7637
AND B.DBID = 3629726729
AND E.DBID = 3629726729
AND B.INSTANCE_NUMBER = 1
AND E.INSTANCE_NUMBER = 1
and e.STAT_NAME = ‘session logical reads‘
and b.stat_name = ‘session logical reads‘) Total_rate,
nvl((sqt.cput / 1000000), to_number(null)) CPU_Time_s,
nvl((sqt.elap / 1000000), to_number(null)) Elapsed_Time_s,
sqt.sql_id,
decode(sqt.module, null, null, ‘Module: ‘ || sqt.module) SQL_Module,
nvl(st.sql_text, to_clob(‘** SQL Text Not Available **‘)) SQL_Text
from (select sql_id,
max(module) module,
sum(buffer_gets_delta) logicr,
sum(executions_delta) exec,
sum(cpu_time_delta) cput,
sum(elapsed_time_delta) elap
from dba_hist_sqlstat
where dbid = 3629726729
and instance_number = 1
and 7634 < snap_id
and snap_id <= 7637
group by sql_id) sqt,
dba_hist_sqltext st
where st.sql_id(+) = sqt.sql_id
and st.dbid(+) = 3629726729
and (SELECT sum(e.VALUE) - sum(b.value)
FROM DBA_HIST_SYSSTAT b, DBA_HIST_SYSSTAT e
WHERE B.SNAP_ID =7634
AND E.SNAP_ID =7637
AND B.DBID = 3629726729
AND E.DBID = 3629726729
AND B.INSTANCE_NUMBER = 1
AND E.INSTANCE_NUMBER = 1
and e.STAT_NAME = ‘session logical reads‘
and b.stat_name = ‘session logical reads‘) > 0
order by nvl(sqt.logicr, -1) desc, sqt.sql_id)
where rownum < 65and(rownum <= 10
or Total_rate > 1);
# 物理读 TOP 10
select *
from (select sqt.dskr Physical_Reads,
sqt.exec Executions,
decode(sqt.exec, 0, to_number(null), (sqt.dskr / sqt.exec)) Reads_per_Exec ,
(100 * sqt.dskr) /
(SELECT sum(e.VALUE) - sum(b.value)
FROM DBA_HIST_SYSSTAT b, DBA_HIST_SYSSTAT e
WHERE B.SNAP_ID = $P{p_beg_snap}
AND E.SNAP_ID = $P{p_end_snap}
AND B.DBID = 1273705906
AND E.DBID = 1273705906
AND B.INSTANCE_NUMBER = 1
AND E.INSTANCE_NUMBER = 1
and e.STAT_NAME = ‘physical reads‘
and b.stat_name = ‘physical reads‘) Total_rate,
nvl((sqt.cput / 1000000), to_number(null)) CPU_Time_s,
nvl((sqt.elap / 1000000), to_number(null)) Elapsed_Time_s,
sqt.sql_id,
decode(sqt.module, null, null, ‘Module: ‘ || sqt.module) SQL_Module,
nvl(st.sql_text, to_clob(‘** SQL Text Not Available **‘)) SQL_Text
from (select sql_id,
max(module) module,
sum(disk_reads_delta) dskr,
sum(executions_delta) exec,
sum(cpu_time_delta) cput,
sum(elapsed_time_delta) elap
from dba_hist_sqlstat
where dbid = 1273705906
and instance_number = 1
and $P{p_beg_snap} < snap_id
and snap_id <= $P{p_end_snap}
group by sql_id) sqt,
dba_hist_sqltext st
where st.sql_id(+) = sqt.sql_id
and st.dbid(+) = 1273705906
and (SELECT sum(e.VALUE) - sum(b.value)
FROM DBA_HIST_SYSSTAT b, DBA_HIST_SYSSTAT e
WHERE B.SNAP_ID = $P{p_beg_snap}
AND E.SNAP_ID = $P{p_end_snap}
AND B.DBID = 1273705906
AND E.DBID = 1273705906
AND B.INSTANCE_NUMBER = 1
AND E.INSTANCE_NUMBER = 1
and e.STAT_NAME = ‘physical reads‘
and b.stat_name = ‘physical reads‘) > 0
order by nvl(sqt.dskr, -1) desc, sqt.sql_id)
where rownum < 65and(rownum <= 10
or Total_rate > 1);
# 消耗CPU TOP 10
select *
from (select nvl((sqt.elap / 1000000), to_number(null)) Elapsed_Time_s,
nvl((sqt.cput / 1000000), to_number(null)) CPU_Time_s,
sqt.exec Executions,
decode(sqt.exec,
0,
to_number(null),
(sqt.elap / sqt.exec / 1000000)) Elap_per_Exec_s,
(100 *
(sqt.elap / (SELECT sum(e.VALUE) - sum(b.value)
FROM DBA_HIST_SYSSTAT b, DBA_HIST_SYSSTAT e
WHERE B.SNAP_ID = 7396
AND E.SNAP_ID = 7399
AND B.DBID = 1273705906
AND E.DBID = 1273705906
AND B.INSTANCE_NUMBER = 1
AND E.INSTANCE_NUMBER = 1
and e.STAT_NAME = ‘DB time‘
and b.stat_name = ‘DB time‘)))/1000 Total_DB_Time_rate,
sqt.sql_id,
to_clob(decode(sqt.module,
null,
null,
‘Module: ‘ || sqt.module)) SQL_Module,
nvl(st.sql_text, to_clob(‘ ** SQL Text Not Available ** ‘)) SQL_Text
from (select sql_id,
max(module) module,
sum(elapsed_time_delta) elap,
sum(cpu_time_delta) cput,
sum(executions_delta) exec
from dba_hist_sqlstat
where dbid = 65972167
and instance_number = 1
and 7396 < snap_id
and snap_id <= 7399
group by sql_id) sqt,
dba_hist_sqltext st
where st.sql_id(+) = sqt.sql_id
and st.dbid(+) = 1273705906
order by nvl(sqt.cput, -1) desc, sqt.sql_id)
where rownum < 65
and (rownum <= 10 or Total_DB_Time_rate > 1);
# 执行时间 TOP 10
select *
from (select nvl((sqt.elap / 1000000), to_number(null)) Elapsed_Time_s,
nvl((sqt.cput / 1000000), to_number(null)) CPU_Time_s,
sqt.exec Executions,
decode(sqt.exec,
0,
to_number(null),
(sqt.elap / sqt.exec / 1000000)) Elap_per_Exec_s,
(100 *
(sqt.elap / (SELECT sum(e.VALUE) - sum(b.value)
FROM DBA_HIST_SYSSTAT b, DBA_HIST_SYSSTAT e
WHERE B.SNAP_ID = $P{p_beg_snap}
AND E.SNAP_ID = $P{p_end_snap}
AND B.DBID = 1273705906
AND E.DBID = 1273705906
AND B.INSTANCE_NUMBER = 1
AND E.INSTANCE_NUMBER = 1
and e.STAT_NAME = ‘DB time‘
and b.stat_name = ‘DB time‘)))/1000 Total_DB_Time_rate,
sqt.sql_id,
to_clob(decode(sqt.module,
null,
null,
‘Module: ‘ || sqt.module)) SQL_Module,
nvl(st.sql_text, to_clob(‘ ** SQL Text Not Available ** ‘)) SQL_Text
from (select sql_id,
max(module) module,
sum(elapsed_time_delta) elap,
sum(cpu_time_delta) cput,
sum(executions_delta) exec
from dba_hist_sqlstat
where dbid = 1273705906
and instance_number = 1
and $P{p_beg_snap} < snap_id
and snap_id <= $P{p_end_snap}
group by sql_id) sqt,
dba_hist_sqltext st
where st.sql_id(+) = sqt.sql_id
and st.dbid(+) = 1273705906
order by nvl(sqt.elap, -1) desc, sqt.sql_id)
where rownum < 65
and (rownum <= 10 or Total_DB_Time_rate > 1);
查找需要使用绑定变量的sql
select substr(sql_text,1,40), count(*)
from v$sqlarea
group by substr(sql_text,1,40) having count(*) > 50;
再 select sql_text from v$sqlarea where sql_text like ‘insert into test %‘; 找出具体的sql代码
检查Latch的相关SQL
# 查询当前数据库最繁忙的Buffer，TCH(Touch)越大表示访问次数越高
SELECT *
FROM ( SELECT addr,
ts#,
file#,
dbarfil,
dbablk,
tch
FROM x$bh
ORDER BY tch DESC)
WHERE ROWNUM < 11;
# 查看latch的命中率
SQL>SELECT name, gets, misses, sleeps,
immediate_gets, immediate_misses
FROM v$latch
WHERE name = ‘cache buffers chains‘;
#查找数据块中的热点块
SELECT *
FROM (SELECT O.OWNER, O.OBJECT_NAME, O.OBJECT_TYPE, SUM(TCH) TOUCHTIME
FROM X$BH B, DBA_OBJECTS O
WHERE B.OBJ = O.DATA_OBJECT_ID
AND B.TS# > 0
GROUP BY O.OWNER, O.OBJECT_NAME, O.OBJECT_TYPE
ORDER BY SUM(TCH) DESC)
WHERE ROWNUM <= 10;
#根据文件号和块号查找数据库对象
select owner, segment_name, partition_name, tablespace_name
from dba_extents
where relative_fno = &v_dba_rfile and &v_dba_block between block_id and block_id + blocks - 1;
# 如果在Top 5中发现latch free热点块事件时，可以从V$latch_children中查询具体的子Latch信息
SELECT *
FROM (SELECT addr, child#, gets, misses, sleeps, immediate_gets igets,
immediate_misses imiss, spin_gets sgets
FROM v$latch_children
WHERE NAME = ‘cache buffers chains‘
ORDER BY sleeps DESC)
WHERE ROWNUM < 11;
# 查看引起latch: cache buffers chains的sql
SQL> select * from (select
count(*),
sql_id,
nvl(o.object_name,ash.current_obj#) objn,
substr(o.object_type,0,10) otype,
3 4 5 6 CURRENT_FILE# fn,
CURRENT_BLOCK# blockn
from v$active_session_history ash
, all_objects o
where event like ‘latch: cache buffers chains‘
and o.object_id (+)= ash.CURRENT_OBJ#
group by sql_id, current_obj#, current_file#,
current_block#, o.object_name,o.object_type
order by count(*) desc )where rownum <=10;
日常管理
#查看当前用户的trace文件
SELECT u_dump.VALUE
|| ‘/‘
|| db_name.VALUE
|| ‘_ora_‘
|| v$process.spid
|| NVL2 (v$process.traceid, ‘_‘ || v$process.traceid, NULL)
|| ‘.trc‘
"Trace File"
FROM v$parameter u_dump
CROSS JOIN
v$parameter db_name
CROSS JOIN
v$process
JOIN
v$session
ON v$process.addr = v$session.paddr
WHERE u_dump.name = ‘user_dump_dest‘
AND db_name.name = ‘db_name‘
AND v$session.audsid = SYS_CONTEXT (‘userenv‘, ‘sessionid‘)
#查询某段时间内执行过的sql
select a.sql_id,dbms_lob.substr(b.sql_text,4000,1) from dba_hist_active_sess_history a, dba_hist_sqltext b
where sample_time between to_date(‘20100930:09:00‘,‘yyyymmdd:hh24:mi‘)
and to_date(‘20100930:09:01‘,‘yyyymmdd:hh24:mi‘) and b.sql_id=a.sql_id
union all
select a.sql_id ,dbms_lob.substr(b.sql_text,4000,1)from v$active_session_history a ,v$sqlarea b
where sample_time between to_date(‘20100930:09:00‘,‘yyyymmdd:hh24:mi‘) and
to_date(‘20100930:09:01‘,‘yyyymmdd:hh24:mi‘) and b.sql_id=a.sql_id
由于v$active_session_history和dba_hist_active_sess_history的数据来源于awr和ash采样，记录并不完全，故查询结果并不准确。
#查看sql的实际执行计划
SELECT sql_id, address, hash_value FROM v$sql
WHERE sql_text like ¨%TAG%¨;
SQL_ID ADDRESS HASH_VALUE
-------- -------- ----------
40qhh45kcnfbv 82157784 1224822469
#通过sqlid查询库缓冲区中的sql执行计划
SELECT * FROM TABLE(dbms_xplan.display_cursor(‘40qhh45kcnfbv‘,0));
# 查找你的session信息
SELECT SID, OSUSER, USERNAME, MACHINE, PROCESS
FROM V$SESSION WHERE audsid = userenv(‘SESSIONID‘);
# 当machine已知的情况下查找session
SELECT SID, OSUSER, USERNAME, MACHINE, TERMINAL
FROM V$SESSION
WHERE terminal = ‘pts/tl‘ AND machine = ‘rgmdbs1‘;
# 查找当前被某个指定session正在运行的sql语句。寻找被指定session执行的SQL语句是一个公共需求，如果session是瓶颈的主要原因，那根据其当前在执行的语句可以查看session在做些什么。 假设sessionID为100
select b.sql_text
from v$session a,v$sqlarea b
where a.sql_hashvalue=b.hash_value and a.sid=100
#查看sql执行状态
select status,last_call_et,event from v$session where sid=&id;
#查看客户端和应用信息
select osuser,machine,terminal,process,program,client_info,action,module from v$session
where sid=&id and seq#=&seq
#查看会话消耗资源的情况， 以CPU资源为例，不同的资源可以根据v$statname和v$sesstat关联进行查询，常用的有session logical reads, CPU used by this session, db block changes, redo size,
physical writes, parse count (hard), parse count (total), sorts (memory), and sorts (disk)等
select a.sid,spid,status,substr(a.program,1,40) prog,a.terminal,osuser,c.value/60/100 value,d.name
from v$session a,v$process b,v$sesstat c,v$statname d
where d.name=‘CPU used by this session‘
and c.sid=a.sid and a.paddr=b.addr and d.statistic#=c.statistic#
order by c.value desc
注意:v$sysstat 和v$sesstat差别如下：
v$sesstat只保存session数据，而v$sysstat则保存所有sessions的累积值。
v$sesstat只是暂存数据，session退出后数据即清空。v$sysstat则是累积的，只有当实例被shutdown才会清空。
v$sesstat不包括统计项名称，如果要获得统计项名称则必须与v$sysstat或v$statname连接查询获得。
#通过sqlid查询库AWR中的sql执行计划
SELECT * FROM table (DBMS_XPLAN.DISPLAY_AWR (‘40qhh45kcnfbv‘));
#查看某用户的PID和SPID
select pid,spid from v$process
where addr in (select paddr from v$session where username=‘SYSTEM‘);
#查看隐含参数
select x.ksppinm name, y.ksppstvl value, x.ksppdesc describ
from sys.x$ksppi x , sys.x$ksppcv y
where x.indx = y.indx
and x.ksppinm like ‘%&par%‘;
#查看对象大小，对象大小以已分配的extent统计
select segment_name, bytes/1024/1024 MB
from user_segments
where segment_type = ‘TABLE‘;
或者
Select SEGMENT_NAME,Sum(bytes)/1024/1024 From User_Extents where segment_name=‘BIG‘ group by segment_name;
#查看等待事件的详细情况
create or replace procedure WaitHistogram(pFilter varchar2)
is
vTotalWaitCount integer;
cursor rec_cur is
select rpad(substr(event,1,40),42) event,
lpad(to_char(wait_time_MILLI,999999999.99),13) wtm,
lpad(to_char(wait_count,9999999999.99),13) wct,
100*(sum(wait_count) over(order by event,wait_time_milli)) pct_rt
from v$event_histogram where event=pFilter
order by 1,2;
c_event varchar2(100);
c_wtm varchar2(100);
c_wct varchar2(100);
c_pct_rt number(20,2);
begin
select sum(wait_count) into vTotalWaitCount from v$event_histogram where event=pFilter;
dbms_output.enable(800000);
dbms_output.put_line(rpad(‘event‘,45)||‘Wait time Wait count Pct_rt‘);
open rec_cur;
fetch rec_cur into c_event,c_wtm,c_wct,c_pct_rt;
while rec_cur%found loop
dbms_output.put_line(c_event||‘ ‘||c_wtm||‘ ‘||c_wct||‘ ‘||to_char((c_pct_rt/vTotalWaitCount),0999.99));
fetch rec_cur into c_event,c_wtm,c_wct,c_pct_rt;
end loop;
close rec_cur;
end ;
/
exec WaitHistogram(pfilter=>‘gc buffer busy‘);
# 查看表的统计信息
select table_name,num_rows,blocks,empty_blocks,avg_space,chain_cnt,avg_row_len,global_stats,user_stats,sample_size,to_char(last_analyzed,‘yyyy-mm-dd hh24:mi:ss‘)
from dba_tables where owner = upper(nvl(‘&Owner‘,user)) and table_name=upper(‘&table_name‘);
# 查看分区的统计信息
select table_name,PARTITION_NAME ,composite,SUBPARTITION_COUNT,num_rows,blocks,empty_blocks,avg_space,chain_cnt,avg_row_len,global_stats,user_stats,sample_size,to_char(last_analyzed,‘yyyy-mm-dd hh24:mi:ss‘)
from dba_tab_partitions where and table_name=upper(‘&table_name‘);
# 查看子分区的统计信息
select table_name,PARTITION_NAME ,subpartition_name,subpartition_position,num_rows,blocks,empty_blocks,avg_space,chain_cnt,avg_row_len,global_stats,user_stats,sample_size,to_char(last_analyzed,‘yyyy-mm-dd hh24:mi:ss‘)
from dba_TAB_SUBPARTITIONS where table_name=upper(‘&table_name‘);
#查看列上的统计信息
select
COLUMN_NAME,
decode(t.DATA_TYPE,
‘NUMBER‘,t.DATA_TYPE||‘(‘||
decode(t.DATA_PRECISION,
null,t.DATA_LENGTH||‘)‘,
t.DATA_PRECISION||‘,‘||t.DATA_SCALE||‘)‘),
‘DATE‘,t.DATA_TYPE,
‘LONG‘,t.DATA_TYPE,
‘LONG RAW‘,t.DATA_TYPE,
‘ROWID‘,t.DATA_TYPE,
‘MLSLABEL‘,t.DATA_TYPE,
t.DATA_TYPE||‘(‘||t.DATA_LENGTH||‘)‘) ||‘ ‘||
decode(t.nullable,
‘N‘,‘NOT NULL‘,
‘n‘,‘NOT NULL‘,
NULL) col,
NUM_DISTINCT,
DENSITY,
NUM_BUCKETS,
NUM_NULLS,
GLOBAL_STATS,
USER_STATS,
SAMPLE_SIZE,
HISTOGRAM,
AVG_COL_LEN,
to_char(t.last_analyzed,‘yyyy-mm-dd hh24:mi:ss‘)
from dba_tab_columns t
where
table_name = upper(‘&Table_name‘)
and owner = upper(nvl(‘&Owner‘,user));
# 查看分区表列上的统计信息
select
TABLE_NAME,
PARTITION_NAME,
COLUMN_NAME,
NUM_DISTINCT,
DENSITY,
NUM_BUCKETS,
NUM_NULLS,
GLOBAL_STATS,
USER_STATS,
SAMPLE_SIZE,
to_char(t.last_analyzed,‘YYYY-MM-DD HH24:MI:SS‘)
from
dba_PART_COL_STATISTICS t
where
table_name = upper(‘&Table_name‘)
and owner = upper(nvl(‘&Owner‘,user))
/
# 查看子分区上列的统计信息
select
p.PARTITION_NAME,
t.SUBPARTITION_NAME,
t.COLUMN_NAME,
t.NUM_DISTINCT,
t.DENSITY,
t.NUM_BUCKETS,
t.NUM_NULLS,
t.GLOBAL_STATS,
t.USER_STATS,
t.SAMPLE_SIZE,
to_char(t.last_analyzed,‘YYYY-MM-DD HH24:MI:SS‘)
from
dba_SUBPART_COL_STATISTICS t,
dba_tab_subpartitions p
where
t.table_name = upper(‘&Table_name‘)
and t.owner = upper(nvl(‘&Owner‘,user))
and t.subpartition_name = p.subpartition_name
and t.owner = p.table_owner
and t.table_name=p.table_name;
#索引的统计信息
select
INDEX_NAME,
UNIQUENESS,
BLEVEL BLev,
LEAF_BLOCKS,
DISTINCT_KEYS,
NUM_ROWS,
AVG_LEAF_BLOCKS_PER_KEY,
AVG_DATA_BLOCKS_PER_KEY,
CLUSTERING_FACTOR,
GLOBAL_STATS,
USER_STATS,
SAMPLE_SIZE,
to_char(t.last_analyzed,‘YYYY-MM-DD HH24:MI:SS‘)
from
dba_indexes t
where
table_name = upper(‘&Table_name‘)
and table_owner = upper(nvl(‘&Owner‘,user));
#查看分区索引的统计信息
select
i.INDEX_NAME,
i.COLUMN_NAME,
i.COLUMN_POSITION,
decode(t.DATA_TYPE,
‘NUMBER‘,t.DATA_TYPE||‘(‘||
decode(t.DATA_PRECISION,
null,t.DATA_LENGTH||‘)‘,
t.DATA_PRECISION||‘,‘||t.DATA_SCALE||‘)‘),
‘DATE‘,t.DATA_TYPE,
‘LONG‘,t.DATA_TYPE,
‘LONG RAW‘,t.DATA_TYPE,
‘ROWID‘,t.DATA_TYPE,
‘MLSLABEL‘,t.DATA_TYPE,
t.DATA_TYPE||‘(‘||t.DATA_LENGTH||‘)‘) ||‘ ‘||
decode(t.nullable,
‘N‘,‘NOT NULL‘,
‘n‘,‘NOT NULL‘,
NULL) col
from
dba_ind_columns i,
dba_tab_columns t
where
i.table_name = upper(‘&Table_name‘)
and owner = upper(nvl(‘&Owner‘,user))
and i.table_name = t.table_name
and i.column_name = t.column_name
order by index_name,column_position;
# 查看子分区索引的统计信息
select
t.INDEX_NAME,
t.PARTITION_NAME,
t.SUBPARTITION_NAME,
t.BLEVEL BLev,
t.LEAF_BLOCKS,
t.DISTINCT_KEYS,
t.NUM_ROWS,
t.AVG_LEAF_BLOCKS_PER_KEY,
t.AVG_DATA_BLOCKS_PER_KEY,
t.CLUSTERING_FACTOR,
t.GLOBAL_STATS,
t.USER_STATS,
t.SAMPLE_SIZE,
to_char(t.last_analyzed,‘MM-DD-YYYY‘)
from
dba_ind_subpartitions t,
dba_indexes i
where
i.table_name = upper(‘&Table_name‘)
and i.table_owner = upper(nvl(‘&Owner‘,user))
and i.owner = t.index_owner
and i.index_name=t.index_name;
#正在运行的存储过程
col name format a56
select name
from v$db_object_cache
where locks > 0 and pins > 0 and type=‘PROCEDURE‘;
select sid,name from v$access;
SELECT s.SID, s.OSUSER, s.USERNAME, s.MACHINE, s.PROCESS,a.object FROM V$SESSION s ,v$access a, v$db_object_cache d WHERE s.sid = a.sid and a.object=d.name and d.type=‘PROCEDURE‘;
# 查询外键约束(查scott用户emp表的所有父表)
set linesize 120
col owner for a8
col table_name for a12
col constraint_name for a20
col column_name for a20
select c.constraint_name,cc.column_name,rcc.owner,rcc.table_name,rcc.column_name
from dba_constraints c,dba_cons_columns cc,dba_cons_columns rcc
where c.owner=‘SCOTT‘
and c.table_name=‘EMP‘ and c.constraint_type=‘R‘ and c.owner=cc.owner
and c.constraint_name=cc.constraint_name and c.r_owner=rcc.owner and c.r_constraint_name=rcc.constraint_name
and cc.position=rcc.position
order by c.constraint_name,cc.position;
# 查询连接到某表的所有外键(查HR用户下EMPLOYEES表的所有子表)
set linesize 120
col owner for a8
col pk_tab for a12
col fk_tab for a12
col pk for a15
col fk for a15
col pk_col for a12
col fk_col for a12
select rcc.owner,rcc.table_name pk_tab,rcc.constraint_name pk,rcc.column_name pk_col,c.table_name fk_tab,c.constraint_name fk,cc.column_name fk_col
from dba_constraints c,dba_cons_columns cc,dba_cons_columns rcc
where c.owner=‘HR‘ and rcc.table_name=‘EMPLOYEES‘
and c.constraint_type=‘R‘
and c.owner=cc.owner and c.constraint_name=cc.constraint_name
and c.r_constraint_name=rcc.constraint_name
order by c.constraint_name,cc.position;
# 查询主键唯一键约束(HR用户Employees表的主键唯一键约束)
set linesize 120
col constraint_type for a8
col constraint_name for a20
col column_name for a20
select c.constraint_name,c.constraint_type,cc.column_name
from dba_constraints c,dba_cons_columns cc
where c.owner=‘HR‘ and c.table_name=‘EMPLOYEES‘ and c.owner=cc.owner and
c.constraint_name=cc.constraint_name and c.constraint_type in (‘P‘,‘U‘)
order by c.constraint_type,c.constraint_name,cc.position;
#监控使用并行的sql
set pages 0
column sql_test format a60
select p.server_name,
sql.sql_text
from v$px_process p, v$sql sql, v$session s
WHERE p.sid = s.sid
and p.serial# = s.serial#
and s.sql_address = sql.address
and s.sql_hash_value = sql.hash_value
/
#查看并行进程的会话统计信息,如物理读
SELECT QCSID, SID, INST_ID "Inst", SERVER_GROUP "Group", SERVER_SET "Set",
NAME "Stat Name", VALUE
FROM GV$PX_SESSTAT A, V$STATNAME B
WHERE A.STATISTIC# = B.STATISTIC# AND NAME LIKE ‘PHYSICAL READS‘
AND VALUE > 0 ORDER BY QCSID, QCINST_ID, SERVER_GROUP, SERVER_SET;
#查看并行进程的系统统计信息
SELECT NAME, VALUE FROM GV$SYSSTAT
WHERE UPPER (NAME) LIKE ‘%PARALLEL OPERATIONS%‘
OR UPPER (NAME) LIKE ‘%PARALLELIZED%‘ OR UPPER (NAME) LIKE ‘%PX%‘;
#查看隐藏参数
col KSPPINM for a40
col KSPPDESC for a40
SELECT ksppinm, ksppstvl, ksppdesc
FROM x$ksppi x, x$ksppcv y
WHERE x.indx = y.indx AND ksppinm = ‘_db_block_hash_buckets‘
#查看本会话消耗的资源
select sn.statistic#,
sn.name,
m.value
from v$statname sn, v$mystat m
where sn.statistic# = m.statistic#
感谢$无为公子、萧雨、惜分飞的帮助
参考至:http://mlxia.iteye.com/blog/741227
http://blog.csdn.net/soulcq/article/details/5418085
http://www.dbtan.com/2010/05/latch-free.html
http://www.2cto.com/database/201107/96826.html
http://blog.csdn.net/robinson1988/article/details/4793962
http://blog.csdn.net/tianlesoftware/article/details/5263238
http://www.laoxiong.net/dbms_stats_and_analyze_and_global_statistics.html
http://www.laoxiong.net/wp-content/uploads/2008/12/sosi.sql
http://www.cnblogs.com/caizhimin816/archive/2012/12/21/2827375.html
http://oracledoug.com/px.pdf
http://www.linuxeden.com/html/database/20111127/117134.html
https://support.oracle.com/CSP/main/article?cmd=show&type=NOT&id=1019722.6
http://docs.oracle.com/cd/E11882_01/server.112/e25523/parallel006.htm#VLDBG1513
DBA日常维护SQL整理(原创)