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Why SQL Test Case Builder? For most SQL problems, the single most important factor for a speedy bug resolution is to obtain a reproducible test case. However, this is normally the longest and most painful step for customers. The goal of the SQL Test Case Builder (TCB) is to automatically gather as much information as … Read more
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
DDE: Problem Key ‘ORA 312’ was flood controlled (0x5) (no incident)
ORA-00312: online log 2 thread 1: ‘/oracle/oradata/icme/redo02.log’
Error 19527 creating/clearing online redo logfile 2
ORA-24247: network access denied by access control list (ACL)
ORA-06512: at “SYS.UTL_TCP”, line 17
ORA-06512: at “SYS.UTL_TCP”, line 267
DEMO 1,How to use oradebug to call OS commands via the database
DEMO 2,Disable sys audit
ORA-39083: Object type JOB failed to create with error:
ORA-00001: unique constraint (SYS.I_JOB_JOB) violated
因安装数据库时启用了ASMM,过了几天发现分配不太理想想禁用ASMM，手动调整shared_pool_size, 这是一个动态参数，修改后立即生效无需重启数据库实例，但修改时遇到了比较奇怪的现象。
今天有个项目系统负载突然变大，查到top sql是一个存储过程,执行计划缺少合理的索引，SQL是个update操作，于是kill 调用的几个session 建立一个索引，结果发现kill几个用户进程后实例挂了.下面是alert日志，可见instance crash前出现过死锁,就是那个update sql Thu Aug 15 11:08:04 2013 ORA-00060: Deadlock detected. More info in file /oracle/admin/icme/udump/icme_ora_24011.trc. Thu Aug 15 11:27:00 2013 ORA-00060: Deadlock detected. More info in file /oracle/admin/icme/udump/icme_ora_26527.trc. Thu Aug 15 11:27:03 2013 ORA-00060: Deadlock detected. More info in file /oracle/admin/icme/udump/icme_ora_26912.trc. Thu Aug 15 11:32:46 2013 ORA-00060: Deadlock detected. More info … Read more
Enabling Listener Trace ,TNS-01251 Oracle version 11g introduced the ADR or Automatic Diagnostic Repository feature,Trying to change the log file using the Lsnrctl utility fails with: TNS-01251: Cannot set trace/log directory under ADR. oracle@db231 trace]$ lsnrctl status LSNRCTL for Linux: Version 11.2.0.3.0 – Production on 15-AUG-2013 14:15:59 Copyright (c) 1991, 2011, Oracle. All rights reserved. … Read more
EXP-00008: ORACLE error 1455 encountered
ORA-01455: converting column overflows integer datatype
EXP-00000: Export terminated unsuccessfully
有时需要在plsql 写一些动态sql,用execute immediate 或dbms_sql 调 用，但是execute immediate 后动态sql 文本的长度限制是多少呢？
It is widely known that the Oracle server uses kslgetl – Kernel Service Lock Management Get Latch function to acquire the latch,oradebug call kslgetl/kslfre can be used to acquire the latch manually. This is very useful to simulate latch related hangs and contention.
今天开发的同事问有个表上的数据为什么删不掉？我看了一下，也就不到100000条数据，表上有外键，等了5分钟hang在那里…
《Know More about Oracle AWR》 姐妹篇，oracle 10g引入，ASH 是性能诊断工具，不像sql trace总是默认打开， 保存历史上发生了什么， 提供比AWR更细粒度的数据，即使当系统负载很高时，它也工作的很好，因为使用类似memcopy的数据收集，不会有太大的额外负担，没用任何类型的数据库lock。 Active(‘Active’ == Non-idle sessions) Session History Licensed as part of the Diagnostic pack,
一段时间以来，Oracle在此领域的解决方案一直是其内置工具Statspack。Oracle数据库10g进行了重大改进：自动工作量存储库（AWR）。AWR与数据库一起安装，不仅捕获统计信息，还捕获捕获的指标。
在分页查询或top n中在oracle 之间的版本使用rownum,row_number..，从12c 提供了offset fetch 的语法，其实这个语法不是什么新鲜玩意，在DB2,MSSQL,MYSQL,PostgreSQL之前也都提供的语法。
在12c以前如果想移动表空间的数据文件首先要offline.再OS mv命令移动离线的数据文件到新路径，Recover datafile[ or tablespace or database] 再Online.从12c 开始可以移动Online 的数据文件了。
前两天对oracle数据库(single instance)进行了迁移升级从10.2.0.4 升到11.2.0.3，有一个项目迁完后第二天，cpu负载升到了130更高（16cpus）. 向用户询问后使用上没有改变，平时就几个人使用，而该用户活动会话就有100多个。最在等待CBC latch. 怀疑是执行计划发生了改变。
Database Architecture consists of
1) Container Database (CDB)
2) Pluggable Database (PDB)
# make direcory for backset file and scripts file,in my case /backup/db_bak cd /backup/db_bak mkdir scripts logs rman # the following is contents of rman_backup_sh vi /backup/db_bak/scripts/rman_backup_sh #!/bin/bash # author: anbob.com # desc: rman backup database level 0 # contact: weejar@gmail.com export ORACLE_HOME=/oracle/product/11.2.0/db_1 export ORACLE_SID=pora40 RMAN_LOG_FILE=/backup/db_bak/logs/rman_database_backup.`date +%y%m%d%H%M`.out # —————————————————————– # Initialize the log file. # … Read more
当做EXPDP 逻辑备份时常用到FULL=Y 的全库备份,但是有些schema不想每次都备份如一些自带的schemas(如APEX_030200),这时可以使用exclude很方便的排除…