Tips
10 Tips for the Oracle 8i Upgrade Exam
Expert insights for a test that truly tests your knowledge of 8i's many new features.
by Damir Bersinic
1/3/2001 -- As with any company in the software industry, new releases and features help Oracle compete in the marketplace and guarantee a source of revenue. At the same time, it also means that Oracle Certified Professionals (OCPs) will need to upgrade their skills to the newest Oracle releases in order to maintain their certification.
If you are already an Oracle 8 Certified Database Administrator (DBA), you do not need to pass the five exams required for the Oracle 8i DBA certification -- you only need to pass exam 1Z0-020 Oracle 8i: New Features for Administrators (for more information on Oracle 8i OCP DBA requirements, go to http://www.oracle.com and select the link to Education). From a time saving point of view, this is a great alternative. Notice that I did not say it was necessarily an easier way to get your Oracle 8i DBA certification. Oracle's upgrade exams are generally the toughest to pass because they assume so much of the candidate. You must be experienced, knowledgeable, a problem solver and a quick thinker (you have less than two minutes per question). The passing score of 37 out of 54 for this exam is lower than previous upgrade exams (the Oracle 8 New Features exam required a passing score of 54 out of 60), but the questions are not any easier --- probably a bit tougher.
In this article I'll provide some insight into things that you can do and know to have a greater chance of passing the Oracle 8i: New Features for Administrators exam. While I can't tell you what the questions are (the non-disclosure agreement that Oracle has everyone agree to prevents me from doing this), it is possible for me to provide hints and insights into what may make you more successful.
Tip #1: Know What's Changed
This should be a no-brainer; after all, the exam is called "New Features for Administrators. However, this is a rather large body of knowledge that we're talking about. The exam tests your understanding of all new features that have been introduced from the DBA perspective. Just because the focus is on the DBA, it does not mean that you won't be tested on programming elements that were introduced in Oracle 8i -- it simply means you need to know how they affect the DBA and what needs to be done at the database level to make these new features work. So things such as tablespace management, security, networking - the purview of the DBA -- will be tested alongside Advanced Queuing, Java, Dimensions and Hierarchies, and PL/SQL enhancements -- things the programmers and designers deal with.
Tip #2: The Candidate Guide Is Your Friend
Oracle publishes a candidate guide for anyone who wants to become an Oracle Certified Professional. Many of us who have already achieved are OCP DBA certification will often fail to review this handy document figuring we're there already. However, when you decide you want to upgrade your DBA certification to Oracle 8i, you should download the PDF document from Oracle's Web site (see URL above) and go to the last few pages. There you will find the topics that will be tested in the New Features for Administrators exam, necessary insight into the areas you need to focus on. Note that what's listed in the guide is what you will be tested on -- Oracle's pretty good that way. From this, you can determine which areas you have good knowledge of already and which things you need to read up on or get more information about. Hey, if they're going to tell you what you'll be tested on, might as well take the information and make it work for you.
Tip #3: Know What's in the Most Recent Shipping Version
The scope of the exam is vast: It tests your knowledge of ALL new features that Oracle introduced in Oracle 8i. Furthermore, the versions of 8i that you will be tested on are not limited to 8.1.5 or 8.1.6, but may include any new features in any version of Oracle that is shipping at the time you write the exam, including 8.1.7, which was recently introduced. I'm not quite sure when Oracle determines that they will add questions from the most current shipping version in the exam, but be prepared to answer questions on all releases of Oracle 8i. Furthermore, questions about a version-specific feature may also creep into the exam, so knowing, to a certain extent, what has changed between 8.1.5 (Oracle 8i), 8.1.6 (Oracle 8i Release 2) and 8.1.7 (Oracle 8i Release 3) can prove useful.
Tip #4: What's an Object?
If the answer to this question escapes you, read up on it before taking the exam. Oracle introduced support for objects in Oracle 8, and this has been enhanced in Oracle 8i. The exam assumes that you understand the nature of objects within Oracle and when they should be used, as well as how their functionality has been improved in Oracle 8i. So be aware, for example, that you can create temporary LOBs now, which can reduce the requirement to enable redo for LOB manipulation, thereby improving the performance of databases that make use of columns of BLOB, CLOB and NCLOB data types. Also be aware that Oracle objects can have methods and that these are a good way to replace trigger and other code to make database definitions more flexible, portable and useful.
Tip #5: Know Partitions
In Oracle 8, you were first introduced to partitions for tables and indexes. Partitioning makes very large databases (VLDBs), such as those found in data warehousing, become more manageable and perform better. It's one of the key improvements in both Oracle 8 and 8i.
In Oracle 8 you only had the choice of range partitions on basic tables and indexes. In Oracle 8i, partitioning has been greatly improved with the ability to partition Index Organized Tables, tables containing objects, as well as to create hash partitions to increase the speed of retrieval. Furthermore, in Oracle 8i you can also sub-partition tables by range and then by hash, thereby providing the storage predictability of range partitions with the speed of hash partitions. Knowing the rules and how physical storage can be assigned when partitioning a table is very important for the exam. The rules for dropping, adding, splitting and merging partitions should be clear to you, since you will be tested on the management of partitions, both table partitions and index partitions.
Tip #6: Understand Indexing Rules
With the advent of partitions, Oracle also introduced a number of new indexing concepts. These include global and local indexes, as well as pre-fixed and non-prefixed indexes. Finally, we also have partitioned and non-partitioned indexes. As a DBA, knowledge of the rules regarding the different types of indexes and what types can be used when a table is partitioned, sub-partitioned and not partitioned at all is essential.
When trying to keep all this new indexing stuff straight, it helps to remember that there are four basic index types: non-partitioned indexes, plus three types of partitioned indexes, including global prefixed, local prefixed, and local non-prefixed. When choosing the type of index to use on a regular table that is not partitioned, you would typically use a non-partitioned index, like you always have.
When choosing an index to use on a partitioned table, local prefixed indexes are the most efficient because there will be a one-to-one mapping of the data in the table partition to the keys in the index partitions. This is because for a local prefixed index to exist, the start of the index and the column the table is partitioned on are the same, thereby ensuring only the touched partitions are scanned. In other words, local prefixed indexes with the same number of partitions as the table they are based on will ensure that only the required partitions to satisfy the WHERE clause of the SQL statement used to query the database will be scanned and no others, thereby reducing the amount of i/o and making the database run faster.
Having said all that about indexes and partitions, you should also understand how Index Organized Tables work and know that they can now contain secondary indexes and also be partitioned, if they do not contain Lobs
Tip #7: Know How To Get Here from There
It's not surprising that you are expected to know how to take an Oracle database from version 7.3 or 8.0 to Oracle 8i. There are several methods that can be used to do this: Import/Export, the Migration Utility, the Copy Table method, running upgrade scripts, the Oracle Migration Assistant, etc. Each has advantages and disadvantages and may be the correct answer in a given scenario. For example, the Migration Utility and Import/Export can both be used to take a database from Oracle 7.3 to Oracle 8i, but if you're performing the migration on the same server as the original database, you may want to use the Migration Utility, as it will be quicker. However, if you needed to change the Oracle database block size, use the Import/Export method.
Tip #8: Get Hands-On Experience
One of the best ways to prepare for any exam is to use the features that you will be tested on. If you have a data warehouse, play with the new summary management features and materialized views, the query rewrite capability, and so on to improve the performance of your databases while at the same time learning how they work. Instead of using Import/Export or CREATE TABLE AS to move tables from one tablespace to another (or to reorganize storage), use the ALTER TABLE MOVE command and then read up on the benefits of doing so. The new features are there to help and they will make your life as a DBA easier.
If your company has not yet decided to migrate their production systems to Oracle 8i, see if you can convince them to get the software and install it on a test server where you can perform trial migrations of backups of production databases and test the new features. You'll be helping the company in their preparation for the move to Oracle 8i and yourself in your preparation for the exam.
Tip #9: Did I Mention Partitioning?
OK, I did. But this topic deserves a second mention, especially since this topic can pop-up when you least expect it. The vast majority of Oracle's client base today probably does not need the performance gains and benefits that partitioning will provide. At the same time, anyone who has worked in the database field for any length of time will recognize that data never seems to shrink but only expand. Therefore, at some point in the future, you may need to make use of these features to make your database perform faster. Oracle has put a strong emphasis on being able to partition tables and indexes, manage those partitions, use objects within the partitions, and so on. This emphasis is very evident by the questions asked on the exam. Although only one of the 14 objective sections deals with partitioning improvements directly, when it comes to managing indexes, you need to know about global prefixed indexes, which indirectly deal with partitions. For this reason, it is a very good idea to have a thorough understanding of everything related to partitions.
Tip 10: Don't Forget What You Should Already Know
Even though this exam tests your knowledge of what is new in Oracle 8i, it also assumes that you have a complete understanding of what is in Oracle 8. This includes Lobs, Index Organized Tables, Net8, SQL*Plus and PL/SQL, Object Features, and many others. When talking about Recovery Manager (RMAN), for example, Oracle assumes that you are familiar with the way it works and what was available in Oracle 8. As a DBA, you should understand all the functions of Oracle databases. After all, this is an upgrade exam and if you passed the Oracle 8 DBA exams, you should already have a firm grounding in what is available in that version and how those things work.
Bonus Tip: Training Always Helps
Oracle has always been good about providing courses that map to the exam objectives. The Oracle 8i: New Features for Administrators course, available from Oracle University, covers the majority of the material that will be asked on the exam. If possible, you may want to ask your employer if you can take the course. With the right instructor, this can go a long way to preparing you for the exam within in a relatively short time frame (five days).
Some Final Perspective
One question I always get asked is "Is it tough?" The answer is that it depends. If you are comfortable with the new features in the product and have a firm grasp of the DBA responsibilities within an Oracle environment, the exam is not that hard. On the other hand, if you are intending to pass the exam by reading books and not really looking at the software, or don't have a firm grasp of Oracle to begin with, I'd suggest you hold off until you're better prepared.
The exam itself is passable with the right knowledge so
- Read the Candidate Guide.
- Use the features being tested.
- Read the Oracle documentation on the topics tested.
- Make sure you understand partitions.
- Make sure you understand indexes.
Keep these in mind and you'll have a solid foundation for passing. Good luck!! 
Have you taken this exam? Rate it below!
Damir Bersinic is an Infrastructure Consultant with Trecata Corporation, a systems integration consultancy in Toronto, Canada. He has more than 20 years of industry experience and has written a number of books on Oracle, Windows, SQL Server and Active Directory. His most recent book is "Portable DBA: SQL Server" from Osborne McGraw-Hill. He is also an Oracle Certified Professional (DBA), MCSE, MCDBA and MCT. He can be reached by e-mail at .
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