备库open read only报错,经查是有一个trigger在open后触发
Errors in file /oracle/admin/hc0/udump/hc01_ora_25891.trc:ORA-07445: exception encountered: core dump [opiexe()+20504] [SIGSEGV] [Address not mapped to object] [0x0000001D4] [] []ORA-00604: error occurred at recursive SQL level 1ORA-16000: database open for read-only accessSat Sep 21 12:09:50 2013Trace dumping is performing id=[cdmp_20130921120950]** 2013-09-21 12:09:48.649*** SERVICE NAME:(SYS$USERS) 2013-09-21 12:09:48.649*** SESSION ID:(1086.3) 2013-09-21 12:09:48.649kswsupdsvc: unexpected ex
异地restore 报ORA-01180
RMAN-03002: failure of restore command at 08/24/2009 09:43:51ORA-01180: can not create datafile 1ORA-01110: data file 1: '/oradata/ytdb/system01.dbf' catalog start with '/oracle/databackup';run{allocate channel d1 type disk ;allocate channel d2 type disk ;allocate channel d3 type disk ;allocate channel d4 type disk ; restore database ;recover database;}[@more@]
linux RAC 自启动开关
禁止Clusterware在系统重启后自动启动:$ /etc/init.d/init.crs disable在系统正常启动后: 让Clusterware在系统重启后自动启动:$ /etc/init.d/init.crs enable[@more@]
windows 下用 as sysdba登陆报错
sqlnet.ora加入下面SQLNET.AUTHENTICATION_SERVICES= (NTS)NAMES.DIRECTORY_PATH= (TNSNAMES, ONAMES, HOSTNAME) set oracle_sid=xxx[@more@]
timestamp类型的加减运算
SELECT to_char(fapplytime + NUMTODSINTERVAL(3,'day'),'yyyy-mm-dd HH24:mi:ss:ff6'), fapplytime FROM tdeposit where id=376169319; 对numtodesignterval的原版诠释如下: NUMTODSINTERVAL converts n to an INTERVAL DAY TO SECOND literal. The argument n can be any NUMBER value or an expression that can be implicitly converted to a NUMBER value. The argument interval_unit can be of CHAR, VARCHAR2, NCHAR, or NVARCHAR2 datatype. The value for interval_unit specifies the unit of n and must resolve to one
改sga_target的注意事项
尽量不要由高设置,大幅度向下减少,这样容易引起系统kswap占用较多资源,引起系统崩溃[@more@]
通过查询查看sql执行计划
select * from table(dbms_xplan.display_cursor(&sql_id,null,'advanced'));[@more@]
手工在alter.log中产生警告
SQL> exec sys.dbms_system.ksdwrt(2, 'ORA-99999 Just For test');PL/SQL procedure successfully completed.[@more@]
快速释放undo
日常工作中,经常出现undo表空间在某个时间使用量很大后要等待smon进程回收,但是smon进程一般12小时才释放回收一次,有个参数可以直接调用smon进程释放undo表空间alter system set "_smu_debug_mode"=16;[@more@]
ASM磁盘头信息备份,转载
转自http://blueocean926.itpub.net/post/38439/484030使用kfed修复磁盘组DSKGRP2 ASM磁盘分区或者设备文件删除后恢复的方法http://www.itpub.net/viewthread.php?tid=1021898&extra=&page=1[@more@]
job调用存储过程(包含current_timestamp函数)导致插入数据库后,时间不准确
使用job排程执行储过程,procedure 中调用另一个含有current_timestamp的procedure ,居然时间差异很大,应该是跟job的环境设置有关系(早了8小时),我处理的方法是将current_timestamp字段去除,使用表中的默认值sysdate,使用sysdate就完全没问题[@more@]
关于索引是否该rebuild的问题
有几个指标:height应<4,pct_used应>75-90select height,lf_rows,del_lf_rows,btree_space,used_space,pct_used,del_lf_rows/lf_rows radio from index_stats;del_lf_rows有删除行讨论链接参考http://www.itpub.net/thread-1175572-1-2.html[@more@]
SYS_CONNECT_BY_PATH函数在9i,10G下导致执行计划改变
因数据库从9i到10g升级后,带SYS_CONNECT_BY_PATH 函数的sql语句导致执行计划改变原链接地址 http://www.itpub.net/viewthread.php?tid=1174233&extra=&page=1[@more@]
service network restart 命令使用时导致集群该节点重启
在oracle RAC环境下,不能任意使用此命令[@more@]
oracle md5函数
CREATE OR REPLACE FUNCTION fn_md5(input_string IN VARCHAR2) RETURN VARCHAR2 IS raw_input RAW(128) := UTL_RAW.cast_to_raw(input_string); decrypted_raw RAW(2048); error_in_input_buffer_length EXCEPTION;BEGIN DBMS_OBFUSCATION_TOOLKIT.md5(input => raw_input, checksum => decrypted_raw); RETURN LOWER(RAWTOHEX(decrypted_raw));END;[@more@]