11g OCM Upgrade Exam Tips

之前有网友向我咨询一些11g  OCM one day Upgrade Exam升级考试的应试技巧, 我在不违反保密协议的前提下给出了一些建议。

 

总体来说11g OCM的考试要比10g在难度上高出不少,且因为涉及到大量11g的新特性,在国内11g中文资料较为匮乏的大环境下,为考试所要做的准备工作量还是不小的。
我是从2011年的1月开始准备考试,2个月里整理测试了不少11g新特性, 也写了一些11g新特性的相关专题文章(你可以在oracledatabase12g.com 我的个人博客上搜索到),2011年3月11日参加考试并成功通过的, 考试前一天都还没睡好,结果当天日本就发生了地震,导致我对这个日期记得特别牢!

 

以下是网友的一些问题及我的建议:
1)请简要介绍下考试环境。比如也是两台机器吗?功能分配是否和10g一样?共4个section,每个分别占用多长时间?

Answer: 是2台PC机,这个在考纲中就有明确说明;其中一台作为OMS。各环节的时间在105分钟-120分钟不等

 

2)在考试中grid control 10.2.0.5版本是已经安装好了,还是需要自己安装?还是已经安装了10.2.0.1版本然后要求考生升级到10.2.0.5?然后在另外一台机器上安装agent?10g中装完agent直接就可以使用了,配置agent不知道考试什么?

Answer:不需要自己安装;agent要自己安装,所以去详细了解下agent的安装吧,这个环节很重要!

 

3)下午的考试是不是使用上午的冷备份?我一直比较奇怪,为什么要考试冷备份?

Answer:和10g一样会出现需要恢复的场景

 

4)dataguard的新特性基本都考到了,observer在哪台机器上启动?使用grid control做这一部分好,还是使用sql*plus命令行手动做这个比较好?还是使用dgmgrl命令行?这一部分我在10g的考试中,因为不相信grid control的稳定性,选择了使用sql*plus做,结果时间非常紧张,在最后一分钟才做完。考试结束以后,我想这部分就是设计让考生使用grid control做的,不知道理解的对不对。11g的考试中需要注意哪些?

Answer: 我建议用SQLPLUS+DGMGRL,你可以用11g的duplicate standby from active database特性,很方便。可以参考我的文章《Duplicate standby database from active database》http://www.oracledatabase12g.com/archives/duplicate-standby-database-from-active-database.html

 

5)这次考试有没有考到streams?10g考纲里是有的,但是没有考到。

Answer:有STREAMS,而且并不简单;重点复习或者放弃。

 

6)要在两台oel之间配置NFS,然后考试Create and Manage a tablespace that uses NFS mounted file system file?还是NFS已经配置好了?

Answer:NFS帮你都配好了,你只需要关心让Oracle用就可以了。

 

7)有没有超出考纲的试题?

Answer: 没有超纲,但有很多Trap

 

8)物化视图有没有考到查询重写?需要troubleshoot的问题是否比较棘手?

Answer:考了

 

9)Create partitioned tables (includes reference and interval partitioning),这个考试创建什么样的分区表?
Answer:这环节并不困难,少有的送分题

 

10)SQL Tuning Advisor和Access Advisor考试形式是什么?使用grid control做好还是用dbms包来做这部分题,哪一个比较好。
Answer:显然是用OMS

 

11)你建议的考试中需要注意的其它问题是什么?
Answer:把知识点弄透彻,因为存在很多陷阱;考试时一定把题目看清楚看透彻,不会做的题目千万不要浪费太久时间。

 

Question:

按照你上次邮件里的指点的方法做了实验,感觉Duplicate standby database from active database的确是最优的可控的搭建dataguard的方法。配合dgmgrl,让一切变得如此简单!没想到能看到你关于这个话题的文档,倍感亲切。
关于dataguard考试,我还做了假想,dataguard应该像10g那样在一台机器上,observer应该部署在与dataguard不同的机器上,就是oms机上。配置observer就是配置tnsnames.ora
snapshot-sb就是一条命令,没有什么说的,前提是主备库配置好闪回数据库。
另外有一个问题请教:dataguard考试中,Configure the data guard environment to reduce overheads of fast incremental backups on the primary database这个问题,我不是非常确定,查了oracle的dataguard概念和管理文档、备份和恢复用户手册以及metalink,还有网上一些文档,没有发现最优方案。可能是11g的active dg还没有大量应用吧。
我想到的方法是在实时应用的备库打开块修改跟踪,然后0级备份,增量备份,但是由于控制文件和spfile文件不能用于主库失败的恢复,在备库做完备份的同时,在主库做控制文件和spfile的备份。但是不知道这样在恢复到主库的时候会不会有问题。对于这个问题,你有好的最佳实践吗?
alter database enable block change tracking using file ‘/u01/app/oracle/oradata/orcl/bct.log';
configure db_unique_name sbdb connect identifier ‘sbdb';
每周日
connect target sys/oracle@sbdb catalog rman/rman@rman
BACKUP AS BACKUPSET INCREMENTAL LEVEL 0 DATABASE PLUS ARCHIVELOG;
connect target sys/oracle@primary catalog rman/rman@rman
backup current controlfile;
backup spfile;
每天
connect target sys/oracle@sbdb catalog rman/rman@rman
BACKUP AS BACKUPSET INCREMENTAL LEVEL 1 DATABASE PLUS ARCHIVELOG;
connect target sys/oracle@primary catalog rman/rman@rman
backup current controlfile
backup spfile;
每周三
connect target sys/oracle@sbdb catalog rman/rman@rman
BACKUP AS BACKUPSET INCREMENTAL LEVEL 1 CUMULATIVE DATABASE PLUS ARCHIVELOG;
connect target sys/oracle@primary catalog rman/rman@rman
backup current controlfile;
backup spfile;

还有:Configure archivelog deletion policy for the dataguard configuration这个问题,我想就用rman的configure分别
在主库上设置
configure archivelog deletion policy to shipped to all standby;

在备库上设置
configure archivelog deletion policy to applied on all standby;
或者
CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO SBT;(or DISK)  (oracle dataguard文档推荐这样设置P170)

对于archivelog删除策略这个问题你怎么看?

最后一个问题:由于streams在工作中用的比较少,我比较生疏。我按照附件中的文档,做了前11个练习。文档中实验的难度是逐渐加深的,我也想都做一遍,但是streams的问题太多了,实验中还不包括流的split和合并。下一步我会花时间把这个问题认真的学习下,眼前要紧的是先把考试过了。你不要告诉我考题,只需要帮我确认考试的难度在哪个区间?比如1-3,7-9还是16-17等。谢谢了。

 

Answer:

关于reduce overhead的问题,我认为你所写的已经足够充分了,但是不知道你是否注意过11.1.0.7上fast incremental backup存在Bug,具体可以参见我的一篇文章:http://www.oracledatabase12g.com/archives/fast-incremental-backup-failed-on-standby-database.html
如果你把附件中的Practice都练习过的话,那么可以说Streams这块准备的比较充分了

我想11g ocm对有经验的DBA而言并非难事,就你目前的复习进度和能力,通过该认证应当是很轻松的事情了。

祝!考试顺利!

 

此外Gavin Soorma是世界上较早通过11g OCM Upgrade考试获得11g大师认证的同仁之一, 他对于这门考试也给出一些应试建议, 引用如下:

 

  • The 11g OCM upgrade exam is a one day exam while the 11g OCM is a two day exam like the 10g exam. It can be a long day between 8-10 hours, so be prepared for it.
  • I have listed the exam topics here which can be also obtained from the OTN site related to Oracle Certification. While preparing, try and cover each and every topic as the exam will basically cover pretty much every exam objective listed.
  • It’s not about what you know – it’s about how fast you can do stuff as time is the essence in this exam. Working under pressure of time is the biggest obstacle I found that I had to cross.
  • Don’t be overwhelmed by the volume of what is asked in the exam. Every skill set will have an “End State” where your database is expected to be in a particular state. Ensure you keep this in mind and while it may not be possible to complete every task, whatever you do, do it well rather than start each task and leave it incomplete because of time constraints.
  • Practice, practice and more practice. Get as much hands-on experience with all the exam topics. Unlike the 11g OCM exam, the 11g OCM Upgrade exam does not cover topics like RAC and ASM. So it should be quite easy to create a database on even a personal laptop and get as much hands on time as possible as your work environment may not offer opportunities to be faced with all the exam objectives in your practical day to day work as a DBA.
  • While doing the practice, time yourself and see how long it takes to perform any of the exam objectives. Try and figure ways to reduce time through your own shortcuts.
  • Also be familiar with the command line option as well using the different API’s and do not just work on performing everything via GUI Enterprise Manager.
  • The documentation is your best friend in the exam. Be fully familiar with it and know very clearly which manual in the documentation set covers which exam topic. Documentation on both Enterprise Manager as well as the Database Server will be provided, but do remember that it is not searchable. So you do not have the luxury of time in the exam to browse through the entire documentation set trying to find what you are looking for.
  • Very Important – Be very familiar with different backup and recovery scenarios. You will be expected to perform recovery and at the end of every skill set your database needs to be in a required End State – so no marks for crashed databases!
  • Remember the Enterprise Manager version is not 11g even though the exam is an 11g exam. You will be provided a 10.2.0.5 Grid Control environment.
  • While the official OCM certification site does state that the database version will be 11g Release 2 on Red Hat Linux 5, the database version that I got at the exam was 11.1.0.7. So not too sure if that was a one-off case or the norm.

 

OTN 的Certification Path认证通道是最权威的OCM考试信息来源,更多信息可以参考:

 Oracle Database 11g Certified Master Upgrade Exam

 

Exam Topics 考试内容大纲如下:

 

 

 

顺便也贴下我的OCM Profile:

11g Oracle Certified Master profiles
10g Oracle Certified Master profiles