zhouwf0726的个人空间 http://space.itpub.net/756652 Copyright(C) zhouwf0726的个人空间 SupeSite/X-Space Mon, 13 Oct 2008 14:48:20 GMT Fallacies Of The CBO(zt) http://space.itpub.net/756652/viewspace-470134 oracle系统进行优化的时候，我们希望在数据中执行的语句尽量的少出现hard parse,尽量使用绑定变量，可以减少 绑定变量和BIND PEEKING blogzhouwf0726Sun, 12 Oct 2008 11:11:07 GMT histogram与10053(zt) http://space.itpub.net/756652/viewspace-470124 histogram是 blog zhouwf0726 Sun, 12 Oct 2008 10:55:33 GMT how to show hidden parameter(zt) http://space.itpub.net/756652/viewspace-468211 http://www.itpub.net/viewthread.php?tid=1004815&pid=11762628&page=1&extra=

h...]]> blog zhouwf0726 Tue, 07 Oct 2008 15:07:11 GMT 临时表空间和回滚表空间使用率查询 http://space.itpub.net/756652/viewspace-468168 查询临时表空间和回滚表空间的情况：

--临时表空间使用查询：

11:06:52 SQL> select sess.SID,  segtype, blocks*8/1000 "MB" ,sql_text
11:08:37   2  from v$sort_usage sort, v$sessi...]]> blog zhouwf0726 Tue, 07 Oct 2008 11:34:44 GMT ORA-01975 http://space.itpub.net/756652/viewspace-467963
日常工作中针对分布式事务的处理：

ANSWER
=======

The junk entries In the local transaction Id could have been ca...]]> blog zhouwf0726 Mon, 06 Oct 2008 09:35:18 GMT TUXEDO超时控制全功略(zt) http://space.itpub.net/756652/viewspace-465940 背景：

 

Doc ID: Note:224346.1 blog zhouwf0726 Sat, 27 Sep 2008 14:50:38 GMT 处理分布式事务的in-doubt transaction(zt) http://space.itpub.net/756652/viewspace-465904  

模拟的是分布式事务在2pc提交过程产生in-doubt 的问题解决方式
只能模拟prepare 阶段的in-doubt,commit之后的没法测试，太快。

环...]]> blog zhouwf0726 Sat, 27 Sep 2008 14:19:37 GMT oracle enqueue type http://space.itpub.net/756652/viewspace-464441 This appendix lists Oracle enqueues. Enqueues are shared memory structures (locks) that serialize access to database resources. They can be associated with a session or transaction. Enqueue names are displayed in the blog zhouwf0726 Fri, 26 Sep 2008 11:34:16 GMT Oracle跟踪文件(zt) http://space.itpub.net/756652/viewspace-462946 一、Oracle跟踪文件
    OracleNote 377037.1 Selects...]]> blog zhouwf0726 Fri, 19 Sep 2008 10:16:54 GMT 大量STATSPACK数据统计分析 http://space.itpub.net/756652/viewspace-450246 /*
对于大量数据库的statspack分析我们可以把统计数据统一拿到分析数据库来分析。

以下数据库各个命中率情况摘自sprepins.sql中部分脚本，其他内容我们也可以从该脚本获得

关于sql的消耗情况我们可以从以下两个视图查询：
SELECT * FROM STATS$S...]]> blog zhouwf0726 Thu, 18 Sep 2008 22:28:43 GMT Statspack, Orca and Oracle Database Tuning Statistics(zt) http://space.itpub.net/756652/viewspace-450245 Statspack, Orca and Oracle Database Tuning StatisticsHistorically, statistics for Oracle databases tended to be taken since instance start-up. This was reasonable in the days where databases were shut down regularly for maintenance. However, w...]]> blog zhouwf0726 Thu, 18 Sep 2008 22:11:54 GMT checkpoint详解(zt) http://space.itpub.net/756652/viewspace-442674 checkpoint详解

topcheckpoint扫盲
...]]> blog zhouwf0726 Tue, 09 Sep 2008 18:17:03 GMT latch(zt) http://space.itpub.net/756652/viewspace-442640 WHAT ARE LATCHES AND WHAT CAUSES LATCH CONTENTION

The Oracle RDBMS makes use of different types of locking mechanisms.
They are mainly latches, enqueues, ...]]> blog zhouwf0726 Tue, 09 Sep 2008 13:34:44 GMT Stream推荐安装---10gR2之三 http://space.itpub.net/756652/viewspace-442208   2. D.  Network Connectivity

blog zhouwf0726 Sun, 07 Sep 2008 09:48:48 GMT Stream推荐安装---10gR2之一 http://space.itpub.net/756652/viewspace-442206  

blog zhouwf0726 Sun, 07 Sep 2008 09:46:08 GMT SQL Access Advisor(zt) http://space.itpub.net/756652/viewspace-442204  

SQL Access Advisor in Oracle Database 10g

The SQL Access Advisor makes suggestions about indexes and materialized views which might improve system performance. This article describes how to use the SQL Access Advisor in Orac...]]> blog zhouwf0726 Sun, 07 Sep 2008 09:20:34 GMT WINDOWS平台上扩展SGA (zt) http://space.itpub.net/756652/viewspace-440343 WINDOWS平台上扩展SGA
针对32bit的Windows。Windows2000上不能利用超过4G的内存，一般是2G的内存保留给进程，2G内存保留给核心的。在Windows2000 ...]]> blog zhouwf0726 Mon, 01 Sep 2008 13:25:58 GMT HOW TO READ BLOCK HEADER USING A SAMPLE C PROGRAM http://space.itpub.net/756652/viewspace-439086 Overview
--------

This sample program is   intended to explain how to attach to  shared
memory segment and to  read a block  header using the buffer address.
This program is intended  for...]]> blog zhouwf0726 Sun, 31 Aug 2008 18:14:31 GMT V$LOCK(zt) http://space.itpub.net/756652/viewspace-438697 V$LOCK
Lists the locks currently held by the Oracle database server and outstanding requests for a lock or latch. Any row in V$LOCK either has LMODE=0 (indicating it is a request) or REQUEST=0 (indicating it is a held lock).
blog zhouwf0726 Thu, 28 Aug 2008 20:43:23 GMT alter system switch logfile 和 alter system archive log current 的区别(zt) http://space.itpub.net/756652/viewspace-438647 ALTER SYSTEM SWITCH LOGFILE 对单实例数据库或RAC中的当前实例执行日志切换。(也可以是非归档情况下日志切换)
ALTER SYSTEM ARCHIVE LOG CURRENT 会对数据库中的所有实例执行日志切换。


blog zhouwf0726 Thu, 28 Aug 2008 12:21:58 GMT Understanding System Statistics(zt) http://space.itpub.net/756652/viewspace-434830 Understanding System Statistics
by Jonathan Lewis

blog zhouwf0726 Tue, 26 Aug 2008 22:54:14 GMT 10g NewFeatures学习笔记(转) http://space.itpub.net/756652/viewspace-242155 2007.11.05

一、Automatic Shared Memory Management(ASMM)

1...]]> blog zhouwf0726 Tue, 12 Aug 2008 16:08:13 GMT