Welcome to the 103^rd edition of Log Buffer, the weekly review of database blogs.

Starting with Oracle stuff, Chen Shapira (just a simple DBA on a complex production system) is looking for great PL/SQL. Why? To become a better PL/SQL programmer. “But,” she writes, “for PL/SQL , I’m a bit stuck. I can still read my own code for bad examples, but where can I find examples for great code?  . . .  Somehow, there is simply no open-source code written in PL/SQL that I can read to get a good idea of how PL/SQL should be written.” Niall Litchfield recommends the contents of $ORACLE_HOME/rdbms/admin. Any other ideas to help Chen?

There was no shortage of people offering their help, as always. Beginning here on the Pythian blog, Grégory Guillou posted the fifth of his ten-part series on Oracle silent mode, this part covering adding a node to a 10.2 RAC. Says Grégory, “Even if you don’t leverage RAC’s ability to add or remove nodes to gain in agility, it’s still very likely you’ll come to these techniques when you want to upgrade some of your Servers or Operating Systems.” The post includes links to the earlier articles in the series.

On his Core IT for geeks and pros, Tanel Poder expounds another use case for WaitProf. He begins, “I recently diagnosed a performance issue where the ‘events in waitclass Other’ occasionally took significant part of the session’s response time.  . . . So, what to do when this ‘events in waitclass Other’ wait becomes significant in the response time profile?” This is where waitprof, his custom tool, comes into play.

Jeff Hunter of the So What Co-operative posts Something to be aware of, Part II, in which he and Oracle Support tussle over NUMA in Linux, and where he is heard to say, “My next step is talking to a Duty manager. I really don’t want to do that.” And Part III, which Jeff begins, “I escalated my issue to a duty manager . . .”

On Oracle Applications DBA, Aviad Elbaz knows how to do tricks with a pipe, as he shows in his article on how to execute TKPROF on trace files larger than 2GB. Aviad, I think Bilbo and Gandalf would be proud.

Are you like me, shamefully ignorant about the whole Business Intelligence thing? Do you, too, secretly believe it might be an oxymoron? Mark Rittman is here to help, with an introduction to the Oracle BI Applications.

Vivek Sharma of Database/SQL Experiences informs us that he will be contributing a seminar on “Real Time Performance Tuning” to the very first event mounted by the IOUG (All India Oracle User Group). This is their TechNight, taking place in Hyderabad on Friday, July 18th.

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我们在安装双机热备的数据库时，没必要在2台机器上都安装一次数据库，我们只需在一台数据库主机安装完成后，用rcp的方式把app下的所有文件复制到备机上。以下是主要的安装步骤：

1.在A机（10.203.1.1 db_01）上调整主机内核参数，建立dba group和oracle用户，安装数据库软件，且仅安装数据库软件，create database我们后面可以手工的创建。注意此处建立oracle用户后，需要给oracle设置密码，不然之后做信任机制会有问题。

2.如果有需要版本升级，在安装完成数据库软件后，停lsnr、停dbsnmp，运行升级的runInstaller。由于之前我们没有建库，因此我们在此处也就不必运行$ORACLE_HOME/rdbms/admin/catpatch脚本。

3.在B机（10.203.1.2 db_02）上建立dba group和oracle用户，并且调整主机参数，注意由于需要建双机热备，因此需要保证gid和uid和A机上的一致。

4.在A机的/etc/hosts文件上添加：

在B机的/etc/hosts文件上添加：

5.建立信任机制，在A机的主目录建立.rhosts文件

在B机的主目录建立.rhosts文件

6.测试信任是否建立成功，rlogin不用密码说明设置信任成功：

7.在db_01中将/oracle/app目录拷贝到db_02中：

8.至此，我们已经完成在B机上的数据库安装，可以用rman来测试下数据库启动（因为还未设置pfile，因此用rman启动）：