Monday, September 21, 2009

Teaching table design with EXPECT

The next meeting of the North Texas MySQL Users Group is next Monday and the presentation will be on designing database tables. This is part of a series for novices with MySQL and/or databases. Too often novices commit obvious sins like BIGINTs for any numeric storage field or indexing every column. EXPLAIN is a valuable tool in optimizing SELECT statements but too many DBAs do not discover it until well after they are stuck with a small, unruly group of badly designed tables.

Using EXPLAIN is seen as a 'dark art' by too many and hopefully we can get the novices in North Texas off on the right foot. The meeting is free and starts at 7:00 PM in the Sun Offices, Suite 700, 16000 Dallas Tollway, in Dallas. All are welcome and please try to be a bit early as the downstairs door automatically lock at seven sharp.

Friday, September 18, 2009

What makes a MySQL Developer?

I would like to hear some opinions from the MySQL worldon what knowledge does it require to be a MySQL Developer?

Not the folks who write the MySQL server code but a developer who really knows their stuff when programming with MySQL? The MySQL 5.0 developer exams going under a review. The hands on exam for 5.1, which has been hindered by other chores, is also under construction. But I still have a fundamental question : What makes someone a MySQL Developer?

The course book from the MySQL for Developers class is very thick and filled with a lot of information. It covers a broad spectrum from basic SQL to query optimization. None of it is programming language specific (or covers approaches like using PDO versus mysqli in PHP). And the contents are all good things for anyone trying get data in or out of a MySQL database. But nothing in it says that factor [X] makes a good MySQL Developer.

So what do you look for when hiring a developer for a project that will require heavy MySQL server interaction?

Do you have them optimize queries or do you leave that for a DBA? How much do you value the use or understanding of stored procedures, triggers, or partitioning?

Employers and project managers: If you could use the MySQL Developer certification to screen applicants for a position, what do you want stressed on the exam? And what do you not want stressed?

What knowledge or skills makes the difference between a good and a great MySQL developer?

This is your chance to make your opinions known.

Wednesday, September 16, 2009

Jackalopes and certification questions

Most folks do not know about Jackalopes. They are rabbits, usually Cotton Tails, with antlers from some sort of deer. The one pictured is from the Austin Museum of the Weird. Jackalopes, like unicorns, are fabled creatures may be based on real creatures with injuries, growths, or encounters with taxidermists with too much spare time. What does that have to do with MySQL Certification you ask?

I updating the MySQL Cluster DBA certification exam from the 5.1 to 7.0/7.1 product level. The current exam has not kept pace with the product and the question bank needs updates. The question bank has roughly 180 questions of which we use 130. The extra 50 are the questions that were either not fully developed or did not make it to the exam for a variety of reasons.

Of the 130 that are used, about ten percent are passed by all who take the exam. Roughly half of the questions are passed by at least seventy percent of the certification candidates. And 20% of the questions are getting very low correct rates.

So now I dig into those 20% to see if the questions are wrong, badly phrased, or if I have the question equivalent of a Jackalope. On occasion, despite the best efforts of all involved, a question that will slip through that is just the right mix of obscurity, mangled intention, and linguistic lethargy that combines to make a question that does not test or measure knowledge.

Sometime the questions can be salvaged. Other times they are replaced with new questions, hopefully concerning some stunning new feature in the cluster software. And hopefully we can vanish the Jackalopes from the MySQL exams.

Tuesday, September 1, 2009

Pentaho Solutions: Business Intelligence and Data Warehousing with Pentaho and MySQL

I get several emails each week that are from folks who have the basics mechanics of being a DBA but are looking to learn how to manage data. They can administer a database server but want to know how to get more out of that data. I now have an excellent book for them to refer.

My copy of Pentaho Solutions: Business Intelligence and Data Warehousing with Pentaho and MySQL arrived last week. I need to disclose that I was originally hired by MySQL to replace one of this books authors, Roland Bouman. He told me a year ago that he was working on this book. And I have found that he is always investigating something interesting.

Now to buy a pair of those cheap terabyte disk drives and load up some data.

This book will end up being one of those tomes that DBAs will have dog-eared, stuffed with Post-Ittm notes, and kept within easy grabbing distance from their seat. Anyone interested in Business Intelligence, Data Warehouses, or who has a boss who wants 'more' from their data needs to get a copy of this book. This is one of the clearest, concise book on data warehousing and shows how to quickly get your data ready for deeper analysis. The book is not only a great introduction to the subject but clearly shows how to progress from the basics to advanced analysis.