DBA常用sql

--监控索引是否使用 alter index &index_name monitoring usage; alter index &index_name nomonitoring usage; select * from v$object_usage where index_name = &index_name;

--求数据文件的I/O分布 select df.name,phyrds,phywrts,phyblkrd,phyblkwrt,singleblkrds,readtim,writetim from v$filestat fs,v$dbfile df where fs.file#=df.file# order by df.name;

--求某个隐藏参数的值 col ksppinm format a54 col ksppstvl format a54 select ksppinm, ksppstvl from x$ksppi pi, x$ksppcv cv where cv.indx=pi.indx and pi.ksppinm like '_%' escape '' and pi.ksppinm like '%meer%';

--求系统中较大的latch select name,sum(gets),sum(misses),sum(sleeps),sum(wait_time) from v$latch_children group by name having sum(gets) > 50 order by 2;

--求归档日志的切换频率(生产系统可能时间会很长) select start_recid,start_time,end_recid,end_time,minutes from (select test.*, rownum as rn from (select b.recid start_recid,to_char(b.first_time,'yyyy-mm-dd hh24:mi:ss') start_time, a.recid end_recid,to_char(a.first_time,'yyyy-mm-dd hh24:mi:ss') end_time,round(((a.first_time-b.first_time)*24)*60,2) minutes from v$log_history a,v$log_history b where a.recid=b.recid+1 and b.first_time > sysdate - 1 order by a.first_time desc) test) y where y.rn < 30

--求回滚段正在处理的事务 select a.name,b.xacts,c.sid,c.serial#,d.sql_text from v$rollname a,v$rollstat b,v$session c,v$sqltext d,v$transaction e where a.usn=b.usn and b.usn=e.xidusn and c.taddr=e.addr and c.sql_address=d.address and c.sql_hash_value=d.hash_value order by a.name,c.sid,d.piece;

--求出无效的对象 select 'alter procedure '||object_name||' compile;' from dba_objects where status='INVALID' and wner='&' and object_type in ('PACKAGE','PACKAGE BODY'); / select owner,object_name,object_type,status from dba_objects where status='INVALID';

--求process/session的状态 select p.pid,p.spid,s.program,s.sid,s.serial# from v$process p,v$session s where s.paddr=p.addr;

--求当前session的状态 select sn.name,ms.value from v$mystat ms,v$statname sn where ms.statistic#=sn.statistic# and ms.value > 0;

--求表的索引信息 select ui.table_name,ui.index_name from user_indexes ui,user_ind_columns uic where ui.table_name=uic.table_name and ui.index_name=uic.index_name and ui.table_name like '&table_name%' and uic.column_name='&column_name';

--显示表的外键信息 col search_condition format a54 select table_name,constraint_name from user_constraints where constraint_type ='R' and constraint_name in (select constraint_name from user_cons_columns where column_name='&1'); select rpad(child.table_name,25,' ') child_tablename, rpad(cp.column_name,17,' ') referring_column,rpad(parent.table_name,25,' ') parent_tablename, rpad(pc.column_name,15,' ') referred_column,rpad(child.constraint_name,25,' ') constraint_name from user_constraints child,user_constraints parent, user_cons_columns cp,user_cons_columns pc where child.constraint_type = 'R' and child.r_constraint_name = parent.constraint_name and child.constraint_name = cp.constraint_name and parent.constraint_name = pc.constraint_name and cp.position = pc.position and child.table_name ='&table_name' order by child.owner,child.table_name,child.constraint_name,cp.position;

--显示表的分区及子分区(user_tab_subpartitions) col table_name format a16 col partition_name format a16 col high_value format a81 select table_name,partition_name,HIGH_VALUE from user_tab_partitions where table_name='&table_name'

--使用dbms_xplan生成一个执行计划 explain plan set statement_id = '&sql_id' for &sql; select * from table(dbms_xplan.display);

--求某个事务的重做信息(bytes) select s.name,m.value from v$mystat m,v$statname s where m.statistic#=s.statistic# and s.name like '%redo size%';

--求cache中缓存超过其5%的对象 select o.owner,o.object_type,o.object_name,count(b.objd) from v$bh b,dba_objects o where b.objd = o.object_id group by o.owner,o.object_type,o.object_name having count(b.objd) > (select to_number(value)*0.05 from v$parameter where name = 'db_block_buffers');

--求谁阻塞了某个session(10g) select sid, username, event, blocking_session, seconds_in_wait, wait_time from v$session where state in ('WAITING') and wait_class != 'Idle';

--求session的OS进程ID col program format a54 select p.spid "OS Thread", b.name "Name-User", s.program from v$process p, v$session s, v$bgprocess b where p.addr = s.paddr and p.addr = b.paddr UNION ALL select p.spid "OS Thread", s.username "Name-User", s.program from v$process p, v$session s where p.addr = s.paddr and s.username is not null;

--查会话的阻塞 col user_name format a32 select /*+ rule */ lpad(' ',decode(l.xidusn ,0,3,0))||l.oracle_username user_name, o.owner,o.object_name,s.sid,s.serial# from v$locked_object l,dba_objects o,v$session s where l.object_id=o.object_id and l.session_id=s.sid order by o.object_id,xidusn desc ;

select /*+ rule */ s.username, decode(l.type,'tm','table lock', 'tx','row lock', null) lock_level, o.owner,o.object_name,s.sid,s.serial# from v$session s,v$lock l,dba_objects o where l.sid = s.sid and l.id1 = o.object_id(+) and s.username is not null ;

--求等待的事件及会话信息/求会话的等待及会话信息 select se.sid,s.username,se.event,se.total_waits,se.time_waited,se.average_wait from v$session s,v$session_event se where s.username is not null and se.sid=s.sid and s.status='ACTIVE' and se.event not like '%SQL*Net%' order by s.username; select s.sid,s.username,sw.event,sw.wait_time,sw.state,sw.seconds_in_wait from v$session s,v$session_wait sw where s.username is not null and sw.sid=s.sid and sw.event not like '%SQL*Net%' order by s.username; -

-求会话等待的file_id/block_id col event format a24 col p1text format a12 col p2text format a12 col p3text format a12 select sid,event,p1text, p1, p2text, p2, p3text, p3 from v$session_wait where event not like '%SQL%' and event not like '%rdbms%' and event not like '%mon%' order by event; select name,wait_time from v$latch l where exists (select 1 from (select sid,event,p1text, p1, p2text, p2, p3text, p3 from v$session_wait where event not like '%SQL%' and event not like '%rdbms%' and event not like '%mon%' ) x where x.p1= l.latch#);

--求会话等待的对象 col owner format a18 col segment_name format a32 col segment_type format a32 select owner,segment_name,segment_type from dba_extents where file_id = &file_id and &block_id between block_id and block_id + blocks - 1;

--求buffer cache中的块信息 select o.OBJECT_TYPE, substr(o.OBJECT_NAME,1,10) objname , b.objd , b.status, count(b.objd) from v$bh b, dba_objects o where b.objd = o.data_object_id and o.owner = '&1' group by o.object_type, o.object_name,b.objd, b.status ;

--求日志文件的空间使用 select le.leseq current_log_sequence#, 100*cp.cpodr_bno/le.lesiz percentage_full from x$kcccp cp,x$kccle le where le.leseq =cp.cpodr_seq;

--求等待中的对象 select /*+rule */ s.sid, s.username, w.event, o.owner, o.segment_name, o.segment_type, o.partition_name, w.seconds_in_wait seconds, w.state from v$session_wait w, v$session s, dba_extents o where w.event in (select name from v$event_name where parameter1 = 'file#' and parameter2 = 'block#' and name not like 'control%') and o.owner <> 'sys' and w.sid = s.sid and w.p1 = o.file_id and w.p2 >= o.block_id and w.p2 < o.block_id + o.blocks

--求当前事务的重做尺寸 select value from v$mystat, v$statname where v$mystat.statistic# = v$statname.statistic# and v$statname.name = 'redo size';

--唤醒smon去清除临时段 column pid new_value Smon set termout off select p.pid from sys.v_$bgprocess b,sys.v_$process p where b.name = 'SMON' and p.addr = b.paddr / set termout on oradebug wakeup &Smon undefine Smon

--求回退率 select b.value/(a.value + b.value),a.value,b.value from v$sysstat a,v$sysstat b where a.statistic#=4 and b.statistic#=5;

--求DISK READ较多的SQL select st.sql_text from v$sql s,v$sqltext st where s.address=st.address and s.hash_value=st.hash_value and s.disk_reads > 300;

--求DISK SORT严重的SQL select sess.username, sql.sql_text, sort1.blocks from v$session sess, v$sqlarea sql, v$sort_usage sort1 where sess.serial# = sort1.session_num and sort1.sqladdr = sql.address and sort1.sqlhash = sql.hash_value and sort1.blocks > 200;

--求对象的创建代码 column column_name format a36 column sql_text format a99 select dbms_metadata.get_ddl('TABLE','&1') from dual; select dbms_metadata.get_ddl('INDEX','&1') from dual;

--求表的索引 set linesize 131 select a.index_name,a.column_name,b.status, b.index_type from user_ind_columns a,user_indexes b where a.index_name=b.index_name and a.table_name='&1';

求索引中行数较多的 select index_name,blevel,num_rows,CLUSTERING_FACTOR,status from user_indexes where num_rows > 10000 and blevel > 0 select table_name,index_name,blevel,num_rows,CLUSTERING_FACTOR,status from user_indexes where status <> 'VALID'

--求当前会话的SID，SERIAL# select sid, serial# from v$session where audsid = SYS_CONTEXT('USERENV','SESSIONID');

--求表空间的未用空间 col mbytes format 9999.9999 select tablespace_name,sum(bytes)/1024/1024 mbytes from dba_free_space group by tablespace_name;

--求表中定义的触发器 select table_name,index_type,index_name,uniqueness from user_indexes where table_name='&1'; select trigger_name from user_triggers where table_name='&1';

--求未定义索引的表 select table_name from user_tables where table_name not in (select table_name from user_ind_columns);

--执行常用的过程 exec print_sql('select count(*) from tab'); exec show_space2('table_name'); --求free memory select * from v$sgastat where name='free memory'; select a.name,sum(b.value) from v$statname a,v$sesstat b where a.statistic# = b.statistic# group by a.name;

查看一下谁在使用那个可以得回滚段，或者查看一下某个可以得用户在使用回滚段， 找出领回滚段不断增长的事务，再看看如何处理它，是否可以将它commit，再不行 就看看能否kill它，等等,查看当前正在使用的回滚段的用户信息和回滚段信息: set linesize 121 SELECT r.name "ROLLBACK SEGMENT NAME ",l.sid "ORACLE PID",p.spid "SYSTEM PID ",s.username "ORACLE USERNAME" FROM v$lock l, v$process p, v$rollname r, v$session s WHERE l.sid = p.pid(+) AND s.sid=l.sid AND TRUNC(l.id1(+)/65536) = r.usn AND l.type(+) = 'TX' AND l.lmode(+) = 6 ORDER BY r.name;

--查看用户的回滚段的信息 select s.username, rn.name from v$session s, v$transaction t, v$rollstat r, v$rollname rn where s.saddr = t.ses_addr and t.xidusn = r.usn and r.usn = rn.usn

--生成执行计划 explain plan set statement_id='a1' for &1;

--查看执行计划 select lpad(' ',2*(level-1))||operation operation,options,OBJECT_NAME,position from plan_table start with id=0 and statement_id='a1' connect by prior id=parent_id and statement_id='a1'

--查看内存中存的使用 select decode(greatest(class,10),10,decode(class,1,'Data',2,'Sort',4,'Header',to_char(class)),'Rollback') "Class", sum(decode(bitand(flag,1),1,0,1)) "Not Dirty",sum(decode(bitand(flag,1),1,1,0)) "Dirty", sum(dirty_queue) "On Dirty",count(*) "Total" from x$bh group by decode(greatest(class,10),10,decode(class,1,'Data',2,'Sort',4,'Header',to_char(class)),'Rollback');

--查看表空间状态 select tablespace_name,extent_management,segment_space_management from dba_tablespaces; select table_name,freelists,freelist_groups from user_tables;

--查看系统请求情况 SELECT DECODE (name, 'summed dirty write queue length', value)/ DECODE (name, 'write requests', value) "Write Request Length" FROM v$sysstat WHERE name IN ( 'summed dirty queue length', 'write requests') and value>0;

--计算data buffer命中率 select a.value + b.value "logical_reads", c.value "phys_reads", round(100 * ((a.value+b.value)-c.value) / (a.value+b.value)) "BUFFER HIT RATIO" from v$sysstat a, v$sysstat b, v$sysstat c where a.statistic# = 40 and b.statistic# = 41 and c.statistic# = 42; SELECT name, (1-(physical_reads/(db_block_gets+consistent_gets)))*100 H_RATIO FROM v$buffer_pool_statistics;

--查看内存使用情况 select least(max(b.value)/(1024*1024),sum(a.bytes)/(1024*1024)) shared_pool_used, max(b.value)/(1024*1024) shared_pool_size,greatest(max(b.value)/(1024*1024),sum(a.bytes)/(1024*1024))- (sum(a.bytes)/(1024*1024)) shared_pool_avail,((sum(a.bytes)/(1024*1024))/(max(b.value)/(1024*1024)))*100 avail_pool_pct from v$sgastat a, v$parameter b where (a.pool='shared pool' and a.name not in ('free memory')) and b.name='shared_pool_size';

--查看用户使用内存情况 select username, sum(sharable_mem), sum(persistent_mem), sum(runtime_mem) from sys.v_$sqlarea a, dba_users b where a.parsing_user_id = b.user_id group by username;

--查看对象的缓存情况 select OWNER,NAMESPACE,TYPE,NAME,SHARABLE_MEM,LOADS,EXECUTIONS,LOCKS,PINS,KEPT from v$db_object_cache where type not in ('NOT LOADED','NON-EXISTENT','VIEW','TABLE','SEQUENCE') and executions>0 and loads>1 and kept='NO' order by owner,namespace,type,executions desc; select type,count(*) from v$db_object_cache group by type;

--查看库缓存命中率 select namespace,gets, gethitratio*100 gethitratio,pins,pinhitratio*100 pinhitratio,RELOADS,INVALIDATIONS from v$librarycache

--查看某些用户的hash select a.username, count(b.hash_value) total_hash,count(b.hash_value)-count(unique(b.hash_value)) same_hash, (count(unique(b.hash_value))/count(b.hash_value))*100 u_hash_ratio from dba_users a, v$sqlarea b where a.user_id=b.parsing_user_id group by a.username;

--查看字典命中率 select (sum(getmisses)/sum(gets)) ratio from v$rowcache;

--查看undo段的使用情况 SELECT d.segment_name,extents,optsize,shrinks,aveshrink,aveactive,d.status FROM v$rollname n,v$rollstat s,dba_rollback_segs d WHERE d.segment_id=n.usn(+) and d.segment_id=s.usn(+);

--无效的对象 select owner,object_type,object_name from dba_objects where status='INVALID'; select constraint_name,table_name from dba_constraints where status='INVALID';

--求出某个进程，并对它进行跟踪 select s.sid,s.serial# from v$session s,v$process p where s.paddr=p.addr and p.spid=&1; exec dbms_system.SET_SQL_TRACE_IN_SESSION(&1,&2,true); exec dbms_system.SET_SQL_TRACE_IN_SESSION(&1,&2,false);

--求出锁定的对象 select do.object_name,session_id,process,locked_mode from v$locked_object lo, dba_objects do where lo.object_id=do.object_id;

--求当前session的跟踪文件 SELECT p1.value || '/' || p2.value || '_ora_' || p.spid || '.ora' filename FROM v$process p, v$session s, v$parameter p1, v$parameter p2 WHERE p1.name = 'user_dump_dest' AND p2.name = 'instance_name' AND p.addr = s.paddr AND s.audsid = USERENV('SESSIONID') AND p.background is null AND instr(p.program,'CJQ') = 0;

--求对象所在的文件及块号 select segment_name,header_file,header_block from dba_segments where segment_name like '&1';

--求对象发生事务时回退段及块号 select a.segment_name,a.header_file,a.header_block from dba_segments a,dba_rollback_segs b where a.segment_name=b.segment_name and b.segment_id='&1'

--9i的在线重定义表 /*如果在线重定义的表没有主键需要创建主键*/ exec dbms_redefinition.can_redef_table('cybercafe','announcement'); create table anno2 as select * from announcement exec dbms_redefinition.start_redef_table('cybercafe','announcement','anno2'); exec dbms_redefinition.sync_interim_table('cybercafe','announcement','anno2'); exec dbms_redefinition.finish_redef_table('cybercafe','announcement','anno2'); drop table anno2 exec dbms_redefinition.abort_redef_table('cybercafe','announcement','anno2'); --常用的logmnr脚本(cybercafe) exec sys.dbms_logmnr_d.build(dictionary_filename =>'esal',dictionary_location =>'/home/oracle/logmnr'); exec sys.dbms_logmnr.add_logfile(logfilename=>'/home/oracle/oradata/esal/archive/1_24050.dbf', ptions=>sys.dbms_logmnr.new); exec sys.dbms_logmnr.add_logfile(logfilename=>'/home/oracle/oradata/esal/archive/1_22912.dbf', ptions=>sys.dbms_logmnr.addfile); exec sys.dbms_logmnr.add_logfile(logfilename=>'/home/oracle/oradata/esal/archive/1_22913.dbf', ptions=>sys.dbms_logmnr.addfile); exec sys.dbms_logmnr.add_logfile(logfilename=>'/home/oracle/oradata/esal/archive/1_22914.dbf', ptions=>sys.dbms_logmnr.addfile); exec sys.dbms_logmnr.start_logmnr(dictfilename=>'/home/oracle/logmnr/esal.ora'); create table logmnr2 as select * from v$logmnr_contents; -

-与权限相关的字典 ALL_COL_PRIVS表示列上的授权，用户和PUBLIC是被授予者 ALL_COL_PRIVS_MADE表示列上的授权，用户是属主和被授予者 ALL_COL_RECD表示列上的授权，用户和PUBLIC是被授予者 ALL_TAB_PRIVS表示对象上的授权，用户是PUBLIC或被授予者或用户是属主 ALL_TAB_PRIVS_MADE表示对象上的权限，用户是属主或授予者 ALL_TAB_PRIVS_RECD表示对象上的权限,用户是PUBLIC或被授予者 DBA_COL_PRIVS数据库列上的所有授权 DBA_ROLE_PRIVS显示已授予用户或其他角色的角色 DBA_SYS_PRIVS已授予用户或角色的系统权限 DBA_TAB_PRIVS数据库对象上的所有权限 ROLE_ROLE_PRIVS显示已授予用户的角色 ROLE_SYS_PRIVS显示通过角色授予用户的系统权限 ROLE_TAB_PRIVS显示通过角色授予用户的对象权限 SESSION_PRIVS显示用户现在可利用的所有系统权限 USER_COL_PRIVS显示列上的权限，用户是属主、授予者或被授予者 USER_COL_PRIVS_MADE显示列上已授予的权限，用户是属主或授予者 USER_COL_PRIVS_RECD显示列上已授予的权限，用户是属主或被授予者 USER_ROLE_PRIVS显示已授予给用户的所有角色 USER_SYS_PRIVS显示已授予给用户的所有系统权限 USER_TAB_PRIVS显示已授予给用户的所有对象权限 USER_TAB_PRIVS_MADE显示已授予给其他用户的对象权限，用户是属主 USER_TAB_PRIVS_RECD显示已授予给其他用户的对象权限，用户是被授予者 --如何用dbms_stats分析表及模式？ exec dbms_stats.gather_schema_stats(ownname=>'&USER_NAME',estimate_percent=>dbms_stats.auto_sample_size, method_opt => 'for all columns size auto',degree=> DBMS_STATS.DEFAULT_DEGREE); exec dbms_stats.gather_schema_stats(ownname=>'&USER_NAME',estimate_percent=>dbms_stats.auto_sample_size,cascade=>true); /* FOR ALL [INDEXED | HIDDEN] COLUMNS [size_clause] FOR COLUMNS [size clause] column|attribute [size_clause] [,column|attribute [size_clause]...], where size_clause is defined as size_clause := SIZE {integer | REPEAT | AUTO | SKEWONLY} integer--Number of histogram buckets. Must be in the range [1,254]. REPEAT--Collects histograms only on the columns that already have histograms. AUTO--Oracle determines the columns to collect histograms based on data distribution and the workload of the columns. SKEWONLY--Oracle determines the columns to collect histograms based on the data distribution of the columns */