Saturday, September 13, 2014

Causality and Oracle Expertise

I was involved in a discussion on LinkedIn about the proper timing for an Oracle PL/SQL developer to take the 1Z0-146: Oracle Database 11g: Advanced PL/SQL exam. One of the posters was indicating that while it was appropriate for people new to PL/SQL to study for and take the earlier exam: 1Z0-144: Oracle Database 11g: Program with PL/SQL, they should wait until they have some job experience before taking the 146 exam to earn the Oracle Advanced PL/SQL Developer Certified Professional credential. My own opinion is that waiting until you have a few years of experience is not a bad idea, but it is certainly not something that is necessary for everyone.

The difference between our positions lies in how I view Oracle certifications, their relationship to Oracle knowledge/expertise and (as the title suggests) the causality between the two. Causality is an uncommon word -- even for native English speakers (unless you happen to be a theoretical physicist). Basically it refers to cause and effect. The 'effect' that I am referring to this case is getting employers to recognize you as being knowledgeable about Oracle PL/SQL. There is a widespread belief that earning a given certification will cause employers to view you as being skilled with Oracle.

It does not work that way in the real world. I have interviewed people for Oracle positions many times over the years. I can tell you that I do not automatically assume that because someone has earned a certification that they have all of the relevant skills. A certification means that someone may have a certain set of knowledge. During the interview, I will generally ask questions related to their certifications to get a feel for whether they do or not. If a candidate has the Advanced PL/SQL certification and their resume shows a previous job developing PL/SQL, I will be more likely to believe that they are knowledgeable of the language. I will still ask the candidate several questions to verify that to my satisfaction, however.

Employers cannot trust certifications by themselves because there are too many people who focus on the piece of paper. Their goal is passing the exam rather than learning the information being tested. In researching my study guides I run across brain dump sites all the time. Even people who do not cheat with brain dumps may simply memorize enough facts to pass the exam without actually understanding the material being tested. To be fair, I do not completely trust job experience either. It is possible to be PL/SQL developer for several years and still be really bad at it. I know this is true -- I have worked with some of them.

So... if certifications are not the cause for employers viewing an individual as being knowledgeable about Oracle PL/SQL, then what is? Well -- not to put to fine a point on it, but the cause is becoming knowledgeable about Oracle PL/SQL and being able to demonstrate that knowledge. Candidates should take the time to really learn all of the information being tested in the 1Z0-144 and 1Z0-146 exams. Practice writing PL/SQL blocks. Read tutorials and articles from some of the masters like Steven Feuerstein.This will give you a core of knowledge about the language even if you have no job experience using it. In an interview, you will be able to demonstrate this knowledge when asked questions and that will generate the desired effect.

My approach to certifications is therefore that they should be used as a road map for becoming more knowledgeable. The focus is not on 'passing the test' but rather on 'learning the information'. Focusing on the test is what leads to brain dumps and other cheats. This is counterproductive. If you get hired on the basis of knowledge you do not possess, it will rapidly become obvious. After you pass the exams, keep reading and practicing and learning. In the IT industry, the more you know, the more valuable you are. As a fresher, that knowledge will help you to sit an interview with more confidence that whatever question is asked, you will be able to answer it. Your increased confidence and your knowledge will both do much more to land the job than any piece of paper.

Wednesday, September 3, 2014

1Z0-047 topics being updated on 15-SEP-14. Don't get caught unawares.

A little less than two weeks from the date I'm writing this post, the topics list for the SQL Expert exam, 1Z0-047, will include a number of new subject areas. Simultaneously, two of the legacy topics will be removed, but their impact to test-takers is minimal. I wrote an article discussing the changes in more detail that was just published at CertMag here.

If you have been preparing for this exam and have purchased any existing study materials such as the Oracle Press OCA Oracle Database SQL Certified Expert Exam Guide by Steve O'Hearn or my Study Guide for 1Z0-047: Oracle Database SQL Expert, they will not cover these topics. I am working on a major update to my guide at this time that should be released in a few weeks. I do not have any information about when (or if) Steve's Oracle Press book will be updated to include the new material.  The full list of topics that are being added is:

  • Using pattern matching to recognize patterns across multiple rows in a table
  • Using the PIVOT and UNPIVOT clause
  • Using the SQL row limiting clause
  • Analytical functions including PERCENTILE_CONT, STDDEV, LAG, LEAD
  • Using 12c enhancements to the DEFAULT clause, invisible columns, virtual columns and identity columns
  • Using explicit default values in INSERT and UPDATE statements
  • Using the new index capabilities, such as invisible indexes and multiple indexes on the same columns.
  • Recursively truncate child tables
  • Create a lateral inline view in a query
  • Using the cross_outer_apply_clause

I have updated the 1Z0-047 Exam Detail page on my website to include links to articles for all of the new topics. As so often happens, many of the new links are from +Tim Hall and point to articles on his enormously informative Oracle-Base website. If you are in the final stages of preparing for the SQL Expert exam, you can use these articles along with the Oracle documentation to learn about the additions.

Monday, June 30, 2014

A Lifeline for 9i & 10g OCAs -- Oracle Releases Two OCA-to-OCP Upgrade Options

Historically, Oracle Certified Associates in the Administration track for one release of the database have had only two options for earning the Oracle Certified Professional designation in a later release:
  1. Complete the OCP credential in the release they hold the OCA in. Then take one or more upgrade exams required to bump their OCP to a more current release.
  2. Start from (almost) scratch to earn the OCA and then the OCP in the later release.

Both options require a minimum of two exams. For people that hold the OCA in 9i, the only option since that track was retired last year has been to start over with the OCA in a later release. The introduction of two new exams by the Oracle Certification team has changed the game. Either exam will allow Oracle Certified Associates to upgrade directly to the 11g or 12c Oracle Certified Professional credential. The beta period for the two exams started June 7th:
  • 1Z0-034: Upgrade Oracle9i/10g OCA to Oracle Database 11g OCP
  • 1Z0-067: Upgrade Oracle9i/10g/11g OCA to Oracle Database 12c OCP

I had speculated in a previous blog post that an exam of this type was on the horizon.  I will freely admit that I did not expect OU to create two exams.  I envisioned a single hyped-up version of the 1Z0-060 exam to upgrade candidates to 12c.  I have been developing study guides for these exams since learning of them. After going through their topic lists, I have to wonder if the Oracle Certification team has a recent new hire named Victor Frankenstein, PhD.  1Z0-034 and 1Z0-067 have been pieced together from a number of earlier exams and both are monsters.

While I had not foreseen that OU would create this exam, the topics list matches what I would have expected... had I been expecting anything at all. The test mixes and matches topics from the 11g Admin II (1Z0-053), Admin I (1Z0-052),  and New Features (1Z0-050) exams as well as some from the 10g Admin II (1Z0-043) and New Features (1Z0-040) exams. In all, this exam has 112 topics in 25 sections.  I was stunned by the sheer scope of the exam, until I realized how much 034 is eclipsed by its big brother.

I am reasonably certain that this exam is the largest by topic count of any that I have ever seen from Oracle University.  The test contains over 220 topics under 42 different sections. The topic list contains most everything that is in the 1Z0-034 exam plus a heaping helping from the three 12c administration exams (1Z0-060, 1Z0-062, 1Z0-063).  Oracle professionals who are upgrading from a 9i OCA in particular will be introduced to a wide array of new features.  Candidates preparing for this test need to plan on setting aside a significant amount of study time in order to have a reasonable chance of passing on the first attempt.

As I assumed in my earlier post, neither of these exams eliminates the hands-on training requirement to earn the OCP designation. The new exams will not eliminate that expense, but they can save candidates the expense of at least one exam. In addition, even though both are heavyweights, preparing for a single test will consume less time than preparing for two or more separate ones. If you decide to pursue one of these exams, make sure that you understand from the outset that while they represent a simple way to upgrade your credentials, that is not at all the same thing as an easy way.  You will need to put in some work for these.

Despite their length, I expect that these exams are likely to be fairly popular.  Certainly I see posts by OCAs fairly regularly asking how they can upgrade their credential to a current release of Oracle.

For people who are interested, I have started gathering links to certification-safe study materials on my website for these exams:
1Z0-034: Upgrade Oracle9i/10g OCA to Oracle Database 11g OCP
1Z0-067: Upgrade Oracle9i/10g/11g OCA to Oracle Database 12c OCP

Monday, June 16, 2014

End-of-Chapter Questions and Oracle Certification Preparation

An Oracle exam candidate sent me the following question recently after reading my study guide for the 1Z0-117: Oracle Database 11g Release 2: SQL Tuning exam:

"One thing which I felt is that there should be mock Q&A's or Quiz to test the knowledge gained after finishing each chapter. Having these gives confidence and a practice before going for the exam."

This is a subject that I have a strong opinion about. I thought it deserved a detailed response rather than a brief email. I will state up front that my study guides will never have practice questions in them for several reasons.

The first problem with adding end-of-chapter questions is economic.  My guides present the information on exam topics in a very concise fashion.  Adding questions that adequately cover the same subjects would easily increase the size of my guides by 50-75%. In addition, creating realistic questions and answers is extremely time consuming. Adding these to my guides might well double the amount of my time required to create them. Either the price of the guides would need to increase significantly or I would need to take a reduced royalty payment (from the increased page count) while simultaneously putting in more hours to create each guide. I do not believe that most of my readers would consider the practice questions to be worth a significant price hike. I know that putting in that much more time for less return would make me considerably less interested in spending my time creating them.

The second issue is that I am not a proponent of studying for exams by answering practice questions. The goal of preparing for Oracle certification exams is to gain as much knowledge about the tested topics as possible. Focusing on learning the answers to specific questions is a terrible habit to fall into. For example, imagine a chapter in a certification preparation book that has five end-of-chapter questions. On taking the self test, someone misses four out of five. This strongly implies that they did not understand the material and should re-read the whole chapter more carefully.  However, many candidates will simply look up the sections in the chapter that dealt with the four questions they missed. Once they have memorized all five answers, they will be under the impression that they are fully prepared for the real test. In reality, it is unlikely they fully understand much of the information outside what the questions covered. If the actual test questions are much different from the practice ones, they are likely to get them wrong.

Finally, the largest problem that I have is that end-of-chapter exercises cannot be close enough to the real test to provide candidates a reasonable measure of how prepared they are for the actual exam. There are several reasons for this, including the following:

  • Generally people answer the questions right after reading the material. This does not mean they will recall it days later when sitting for the exam.
  • Often (as noted above), the exam candidate will check their information in the chapter before answering.  The real test is not open book.
  • The questions are grouped together by topic (i.e. what the chapter was about). This makes answering them easier. The real exam jumps around topics randomly.
  • End of chapter questions have no time constraint.
  • There is absolutely no pressure involved. Test takers are not worried about failing, or whether they really put down the right letter on that one really hard question they answered a few minutes ago.

In my opinion, the primary benefit that practice tests provide is to help exam candidates determine if they are ready for the real test. This is the 'confidence' spoken of in the original question. For that confidence to have any basis in reality, the environment of the self test must be as close as possible to the real exam. It should have the same number of questions and the same time limit as the real test. Exam candidates should treat the practice just like the real exam and not peek in the book or use the internet to help on questions they do not know. I would even recommend taking it at the same time of day and at a terminal close to what will be in the testing center. If all of that is done, the results of a well-written practice exam may be a reasonable approximation of what candidates will get on the actual test.

What all of this adds up to is that I do not believe that end-of chapter exercises provide sufficient value to candidates to be worth the considerable effort that would go into adding them. This is not to say they have zero value. End-of-chapter questions make more sense for the Oracle Press series. The chapters in those books are considerably longer than those in my guides. It is possible -- especially late at night -- to read a complete chapter without actually absorbing the information. If you miss a majority of the practice questions and use that feedback to recognize you should re-read the chapter (perhaps the next day), then they can add value to your study process.

Sunday, May 25, 2014

A Flood of 12c Exams on the Horizon?

A handful of certification exams for Oracle 12c have been made available since the database was released to production last year.  The first two exams for the 12c database administration track, 1Z0-061 and 1Z0-062, plus the upgrade exam,1Z0-060, were the first to be released and are available for exam takers now.

The first of the "Essentials" exams targeted at employees of Oracle Partner Network companies followed soon after.  1Z0-497: Oracle Database 12c Essentials, became available as a production exam in early May. The second OPN exam, 1Z0-417: Oracle Database Performance and Tuning Essentials 2015, closes its beta period at the end of May and should be available as a production exam sometime in August. A third OPN exam has just opened its beta period, 1Z0-432: Oracle Real Application Clusters 12c Essentials. This exam has not even made it to the 'Beta Exam' page on the Oracle certification site yet, so I cannot report the anticipated end date.

This makes four 12c exams currently in production and another two in beta. Looking to the future, there are a number of exams in the pipeline to be released to beta later this year. The most clearly defined at the moment is the third exam of the 12c database administrator track, 1Z0-063: Oracle Database 12c: Advanced Administration. This exam was announced at the same time as 1Z0-062, but is sitting in limbo at the moment with a status of 'In development'. Presumably Oracle University is waiting for enough people to earn the 12c OCA certification for the beta exam to have sufficient potential candidates. I expect that they will hit their target number sometime in the next three to four months and open the beta.

On May 22nd, the Oracle Certification team announced three upcoming expert exams on their blog. The test numbers were not provided (although I could make some educated guesses), nor were any dates provided. I would expect all three of them to roll out during the next three to four months.  The announced exams were:

  • Oracle Certified Expert, Oracle Database 12c: Data Guard Administration
  • Oracle Certified Expert, Oracle Database 12c: Performance Management and Tuning
  • Oracle Certified Expert, Oracle Database 12c: RAC and Grid Infrastructure Administration

The final 'exam' is almost pure speculation on my part. Recently there was a discussion on LinkedIn from an Oracle professional who was an Oracle 9i DBA Oracle Certified Associate.  He was looking at his options to upgrade his certification to be a 12c OCP. Currently, that requires two exams (1Z0-062 and 1Z0-063) plus an approved training course. There has never been an upgrade path for OCAs from an earlier release. In the thread, the poster was advised by an Oracle certification official to hold off on his plans because there was an option that would be announced soon that might help him.

No announcement has been made yet (or else I would not need to speculate). The only thing that really makes sense to me, however, would be a for the certification team to create a single exam designed to upgrade from the OCA of one release to the 12c OCP.  The 1Z0-060 exam is made to upgrade from any earlier release and already contains the Core DBA elements. A relatively modest expansion of this exam might be suitable to upgrade candidates who hold an OCA certification for any earlier release. It is certain that the new path would not eliminate the need to satisfy the hands-on training requirement. However, this would at least provide a single-test option for Oracle professionals with an OCA in earlier releases.

Of course that assumes I have guessed correctly.  I make no guarantees.

Sunday, April 20, 2014

Post-Beta changes to 1Z0-062 exam topics

Early-adopter candidates who are preparing for the 1Z0-062 exam -- Oracle Database 12c: Installation and Administration need to be aware that the topics list displayed on the Oracle University website changed on April 11th of this year.  There were a total of four changes made to the list. Two existing topics were removed and two new topics were added.

  • Under the Configuring the Oracle Network Environment section, the "Understand database resident connection pooling" topic was removed.
  • Under the Managing Performance section, the "Use Enterprise Manager to monitor performance" topic was removed.

The removed topics pose no real concern for exam takers.  If you have already prepared for these, it simply means that you will not be asked any questions on them. Knowing more than you need to is not a bad thing after all. However, you do need to modify your study plan to include the following new 1Z0-062 topics:

  • Under the Moving Data section, the topic "Explain the general architecture of Oracle Data Pump" topic has been added.
  • Under the Performing Database Maintenance section, the "Use server-generated alerts" topic has been added.

I published my study guide for this exam on March 10th, so the initial version of the book has the original set of topics.  I have since updated the contents and re-released the study guide.  People who have the Kindle version of the book should get the update automatically if their Kindle is set to auto-update. There is, unfortunately, no equivalent for purchasers of the paperback version.

You can locate information on the two new topics in the Oracle documentation at the following locations:

Explain the general architecture of Oracle Data Pump -- The Oracle Database Utilities 12c Release 1 (12.1) manual contains the following section on Data Pump architecture: Overview of Oracle Data Pump

Use server-generated alerts -- The Oracle Database Administrator's Guide 12c Release 1 (12.1) manual contains the following section on server-generated alerts: Monitoring a Database with Server-Generated Alerts

Neither of these topics are particularly involved and you should be able to adequately prepare for the information you will be tested on by reading the documentation accessible from the above URLs.

Friday, March 21, 2014

Famine to Feast -- Completing four new OCPrep Study Guides

I had big plans over the 2013 holiday season.  Oracle Certification had several new exams in beta. My goal was to write study guides for several of them ahead of time and have everything ready for when they were released to production. Life intruded. Well... strictly speaking, laziness intruded. I found it very easy to spend the holiday season relaxing and very difficult to stare at my laptop for hours on end tippy-tapping out study guides.

The sheer number of options caused a second problem. One of my great strengths is the ability to focus all of my attention on a single objective (something my wife will swear to... and swear at when she is trying to get that attention). Both as a developer and an author, I will sometimes get into a writing fugue where everything around me goes away and my productivity goes through the roof. Unfortunately, when I have numerous competing goals, my ability to focus on just one goes right out the window and I often dither between all of them.

This is not to say that I cannot multitask. I am great at multitasking... just so long as I only have to do one thing at a time.

The upshot is that when the middle of January rolled around, I had three books about a third completed and a list of potential study guides that continued to grow. Around that time, I was offered a voucher for the 1Z0-497: Oracle 12c: Essentials exam. One more target should have increased the logjam of potential study guides. Instead, it ended up fixing the problem. I had a hard deadline for completing that book... the end of the beta. I had scheduled my exam on February 21st, so I had to finish the guide before that date.  So I did.  Two of the study guides that I had partially complete were for 1Z0-060: Upgrade to Oracle Database 12c and 1Z0-062: Oracle Database 12c: Installation and Administration. Much of the research I had done while writing 1Z0-497 was applicable to them -- plus I was on a roll. I finished 1Z0-062 and published it. With my inertia now geared towards writing, I was able to finish the guide for 1Z0-060 and publish it. Then, with all of this Oracle 12c administration research sitting around in my notes (and my head), I went on to write the initial draft of the Oracle Certification Prep study guide for 1Z0-063: Oracle Database 12c: Advanced Administration. Oracle Certification has not even released the beta for that yet... but when they do, I'm ready.

Most of my posts on this blog exist to help Oracle certification candidates or to announce something new in the certification universe. This one was really for me. I will note however, that true to the promise I made in my first post of this blog... it is about Oracle certification, and it is not about what I had for breakfast, where I went on vacation or what amusing things my (nonexistent) cat did today.