Willem Stuursma » certifications

Gecertificeerd door SUN als MySQL 5 databasebeheerder

stuursma — Mon, 28 Jun 2010 12:22:16 +0000

Deze week heb ik eindelijk het tweede deel van het SUN certificatietraject voor MySQL 5 Database Administrator afgerond (Het eerste deel had ik al in augustus 2009 gehaald). Het examen was niet zo heel moeilijk als ze een beetje gewend bent. Dat ben ik wel, ik had ook al de examens voor Certified MySQL 5 Developer gedaan in 2008. Ik had dan ook een score van 94%.

Examen

De minimale score om het examen te halen is 65% van de vragen goed, wat niet zo veel is. De vragen zijn multiple-choice, maar van verschillende soorten. Zo zijn er vragen waarbij je het beste antwoord uit vier of drie antwoorden moet kiezen, maar er zijn ook vragen waarbij je meerdere antwoorden uit drie tot acht mogelijkheden moet kiezen. Gelukkig staat er altijd wel bij hoeveel keuzes je moet maken.

De gemiddelde kans dat je een antwoord goed gokt, is ongeveer 25%. Aangezien het examen uit 65 vragen bestaat, heb je door gokken alleen al 16 vragen goed. Je moet dan nog 27 vragen goed beantwoorden om het examen te halen. Dat is niet erg veel.

Stof

De stof was wel interessant, er wordt redelijk diep ingegaan op de verschillende buffers en caches die MySQL aan boord heeft en hoe je deze kan aanpassen om de performance te verbeteren. Onder andere de record buffer, de table cache, de query cache, de MyISAM key caches, de join en sorteer buffers en de InnoDB buffer pool worden behandeld. Helaas gaat de stof niet zo diep in op replicatie. Er wordt bijvoorbeeld niet eens genoemd dat replicatie alleen de leesoperaties op kan schalen, maar geen invloed heeft op schrijf (write) operaties.

Normalisatie (1NF tot 3NF) komt ook aan bod, net als query-, database- en serveroptimalisatie. Ook gaat het examen behoorlijk diep in op de authenticatie- en authorisatiemechanismen van de MySQL 5 server en op hoe je de server kan beveiligen en kan voorkomen dat mensen bij je data kunnen komen.

Al met al was het wel leerzaam, maar het examen stelde niet zoveel voor.

Sun Certified MySQL 5.0 Database Administrator

stuursma — Mon, 24 Aug 2009 15:24:26 +0000

This week I passed my Sun Certified MySQL 5.0 Database Administrator exam (part one of two). That’s a bit weird: a year ago I did the MySQL 5.0 Developer certification program. So in a few weeks I’ll be a MySQL certified developer and a Sun certified Database Administrator. It’s a bit weird but logical if you think about it: MySQL has been taken over by Sun. Sun has been taken over by Oracle, but the title of “Oracle Certified MySQL Database Administrator” would probably create a computation error in the logic computer that the earth is and mean the end of existence, or something like that.

The exam went pretty much okay, a bit harder than expected. Some questions were not covered in the study guide for certified DBA but were covered in the part for developer certification. Not a big problem because I’ve done that too, but I can imagine that it would be quite hard if I had not. Many questions were three or two questions in one. One question definitely contained an error.

MySQL certification used to be handled through Pearson VUE and scheduling an exam was a breeze back then. Now MySQL certification has been integrated into the Sun certifications. It took me quite some time and some e-mails to figure out how to register for the exam: you have to purchase vouchers at the Sun Training Catalogue (310-810 and 310-811 are the ones you are looking for). Then, you can register at Prometic and use the voucher to pay for the exams. Scheduling the exam works the same way as with Pearson VUE. I took my exam in Assen, The Netherlands at IDée ICT (who makes up those names…). There is still no testing centre in Groningen.

Certification also has become quite more expensive with Sun: it’s now EUR 235,- excluding VAT per exam. With MySQL, it used to be EUR 150,- including taxes.

MySQL Certification

stuursma — Thu, 02 Oct 2008 17:32:00 +0000

When I told my employer that I would like the MySQL Certification Exam, he was quite okay with it and suggested to pay for the book and the exam fees. I looked forward to learning about the lesser used MySQL features: triggers, stored procedures, prepared statements and views. These are not very often used in web development, at least not to my knowledge.

There are three certifications available from MySQL: Developer, Database Administrator and Cluster Administrator. I took the Certified Developer Exam. Each exam is divided into two smaller tests. The first test was very simple, dealing with the basic MySQL features: architecture, connectors, data types, tables, SQL expressions, and basic data manipluations. The most interesting part was the chapter about data types. You usually don’t pay much attention to this but knowing how much storage is required for each data type and knowing the finer details about casting and character sets has proven to be quite handy.

The second test was a bit harder, I was not yet famillair with the possibilities of views, triggers, stores procedures and prepared statements. The parts about joins and subqueries were – again – relatively easy, but I did learn some details about subqueries.

I passed both tests with good grades, but I am not completely satistied. The more advanced features such as stored procedures and triggers are difficult to use in the web applications that I usually work on. Prepared statements looked quite interesting, but unfortunately MySQL has a bug which makes it impossible to use the query cache when using prepared statements. Foreign key constraits and transactions do look interesting, but they’re not dealt with in the Developer Certification program, you have to take the Database Administrator Exam for that. Fortunately, my employer will let me take this exam too.

All in all I am not sure if I can recommend the MySQL Certified Developer Program. If you have a lot of experience in MySQL and work in web development, you might learn a few new things that you can actually use. If you’re relatively new to MySQL, it might be worth it.

Zend Certified PHP Engineer

stuursma — Wed, 10 Sep 2008 19:16:26 +0000

Zend, the company behind PHP, offers a certification program for some time now. You can take an exam and if you pass, you can call yourself a Zend Certified PHP Engineer. I took the exam in July 2006. Back then, it was still a PHP 4.3 exam. These day the exam is worthless: PHP4 has been deprecated and has been superseded by PHP5. However, back in 2006 we were still using it at iWink.

The exam is not very difficult, there are already many web sites explaining the contents of the exam. Taking the exam is a bit cumbersome: there are companies specializing in handling such exams and you have to find one before you can take the exam. Unfortunately, there is no such company in Groningen, so I took the exam in Leeuwarden. After taking the exam, you’ll immediately hear if you passed. I passed on the first try.

After about eight weeks I received a nice package from the United States: my Zend Certified Engineer certificate. It comes framed, very convenient. It has some nice patterns and a huge golden seal, it looks very pretty. Makes for a great decoration.

If the exam worth the effort? You’ll learn the fine details of PHP4: casting and evaluating variables, expressions. If you have a few years of experience you won’t need it. However, it’s not expensive so you can certainly give it a try.

Next: MySQL Certified Developer.