Monday, November 24, 2008

How to find the particular Data Dictionary Table or Dynamic Performance View (V$)?

Dear Blog Readers,

Even though we use some of the important Data Dictionary Tables and Dynamic Performance (V$) views regularly, sometimes we fall short to recall a particular view, i.e. It’s not easy to remember all the dictionary views.

And also, many times, it’s been asked by novice in the OTN Forums that

What is the view to find the information about data files, tablespaces, etc.,?

What are the list of Data Dictionary and Dynamic Performance Views in so and so Oracle Version?

Well, I hope all of we know that there is a data dictionary view called “DICTIONARY”, using this DICTIONARY view, we can find the particular or list of pertinent views of any object in the database.

What is the DICTIONARY view?

The DICTIONARY view is a data dictionary view used to find the list of Data Dictionary and Dynamic Performance (V$) views, and it contains description of data dictionary tables and views. It has two columns, one is ‘TABLE_NAME’ – Name of the object and another column is ‘COMMENTS’ – Text comment on the object.


Name Null? Type
--------------------- -------- --------------


To find the list of data dictionary tables and dynamic performance views.


To find the particular data dictionary table or dynamic performance view.

SELECT * FROM dictionary
WHERE table_name LIKE ‘%Search String%’;


SELECT * FROM dictionary
WHERE table_name LIKE ‘%TABLESP%’;


SQL> SELECT * FROM dictionary
WHERE table_name='DICTIONARY';

Description of data dictionary tables and views

Note: While querying, either the complete word DICTIONARY or first four characters DICT, which is a synonym for DICTIONARY, can be used.

Reference: Oracle® Database Reference 10g Release 2 (10.2)


Sabdar Syed

Sunday, November 9, 2008

Received the Certification Kit of Oracle 10g RAC Expert Exam.

Dear Friends,

After a long wait, I have received the Oracle 10g RAC Expert Certification Kit in my hands today, as I have already taken this exam (1Z0-048) in the month of August-2008. More or less it took more than three months to reach in my hands.

Best of luck everyone who is preparing for the Oracle 10g RAC Expert Exam – 1Z0-048.

Check my other blog post on “How to prepare for 1Z0-048 - Oracle 10g RAC Certified Expert Exam.”

Sabdar Syed,

Saturday, November 8, 2008

How to Get/Gain Real Time Experience/Exposure as a DBA!

Dear Blog Readers,

Every now and then I do receive e-mails from the novice DBAs saying that:

“We could not perform well at the interview, as the questions were too technically based on real time requirements”

“Due to not having real time experience, we failed at the interview to explain the steps/approach to resolve the issue asked”

…… and so on

When I asked them how they prepare and practice the DBA Activities, their response is as follows:

“We brought the Oracle DBA Books written by so and so authors for reference.”

“We only practiced the scenarios what was taught and given as drill in the training institute.”

“We installed the Oracle Software with starter database and get started practicing.”

…… and so on

Well, here are my opinions/suggestions/advices, to them those who are preparing and practicing as above, to gain the real time experience/exposure.

A lot of novice or junior DBAs are out there, who do not know that Oracle offers online documentations on Oracle Database Administration. Rather they simply purchase the available books in the market and get started preparing it. I would advice them to make a habit of reading the Oracle online documentations daily whenever they have time.

As far as I know, in the training institutes, the trainers will only cover the basic and required information up to some level, and discussed the scenarios which are common and basic. I suggest them to not to treat those scenarios as real time questions. The trainers will give you or left up to you to practice and do the drill at your own.

In my opinion, the real time issues are not different from the issues you face while practicing. i.e. fixing the ORA-Errors generated. My strong advice is not to create the database while installing the database, instead create the database manually with very minimal size of SGA and data files. Then, put more load i.e. Insert/Updates/Deletes and look forward for errors and the slowness of database, then fix them and tune the database accordingly. This will not be possible where you have a database with good size of SGA and enough size of data files.

As a real time requirement, install and set up the Oracle Server on Linux Operating System, this confidence will help you in stalling the same on any flavor of the Unix/Linux operating system i.e. Sun Solaris, IBM AIX, HP-UX, Red Hat, Fedora etc, All you need to know that the commands which are specific to OS during the installation.

Never just be satisfied by simply reading the solutions given over the web for such problem which are treated as real time scenarios, rather try to reproduce the problem in your database system, if you can, and do apply the different solutions for that issue.

Do not mug up the procedural steps of any major activity in the database i.e. Upgrade, Migration, Installation, etc.., Even though these are not regular tasks or not possible to do it in the practice systems, I still insist to feel the taste of doing such activities. I can say these are the real time scenarios asked in the interviews.

There are many a lot to say…but at the end what all I can say is…..

Instead of waiting for not having the proper resource to practice the database real time scenarios or activities, at least try to search over the web to get to know what are other real time scenarios, I would strongly advice one to make a habit of regularly visiting OTN Database General Forums, where all kind of basic, advanced, real time, scenarios are questioned and answered by top experts with different and different solutions.

Forum: Database - General

Another good habit is referring the good Oracle Related Blogs to know how they resolved the issues, how they implement the things in their organization with their experience.

List of Oracle-related blogs

Do not forget to read and download this great document "Grow That DBA Career"

Note: Above suggestions are only my views and need not to be the same with others. Whoever have the information of real time ideas/tips and wanted share with the blog readers, they are free allowed to comment directly in the comments section of this blog post. I will also keep update this post with more and more real time experience ideas and tips.

Update: Take a look at the Mr.TOM comment in the comment section below, where he has given his own views on real time tips further to this blog post. Thanks to TOM for adding his views to this post.

Happy Reading !!!

Sabdar Syed,