The MySQL database administration and developing is a very interesting field to be in. If you ever thought about taking your career into that field then here is a guide that might help you get started.

The first thing you should know from an industry point-of-view, there are very very few MySQL DBAs around. The companies that are looking for them range from start-ups that have matured and done well for themselves to large enterprises that have figured that MySQL is by now, safe to use.
Unfortunately, there are a few issues with finding work in MySQL and I will address them in this post.


Firstly, who usually turns out to be a MySQL DBA?

From my experience (and the research done by a recruitment agent who specializes in this niche), you are in one of three roles at the moment:
1) A developer who discovered that MySQL and relational databases are easy to understand (aka …

This is about BOMs – Byte Order Marks.  It is also a follow-up to my previous post.  I discussed Unicode implementations in MySQL, but I omitted considerations about BOMs last time, as I decided to reserve this for a follow-up post (this one).

Wikipedia: has this article.    It explains very well what BOMs are, but I also find it biased. This expresses a “Unix-point-of -view”.  And in particular if it is true that the resistance to using BOMs in the Unix world is partly because various Unix console programs don’t handle them, I don’t think it is a valid reason against BOMs.  I think then that it is rather a valid reason for having those console applications fixed to comply with Unicode …

Working with MySQL Workbench, I was always curious why you couldn’t run a script with a sourcing command, like source or \. command. It raises a 1064 error code, like the one shown in the illustration.

It turned out that there’s a pending feature request to add the ability to run a sourcing command like the following:

SOURCE c:\DATA\some_script.SQL

or,

\. c:\DATA\some_script.SQL

I added my business reason to the bug. Let’s hope the product managers add it quickly.

I had need today to download a version of MySQL 4.1 to test something. The MySQL Developer Zone archives no longer provides any software before 5.0.

While this may have long reached EOL and is no longer support, customers still do run this version of MySQL.

Anybody that can help out with binaries (on several OS’s), it would be appreciated.

Back when MySQL 5.1 was first released, Oracle (which didn’t at the time own Sun or MySQL) wanted to add new InnoDB functionality faster than MySQL could effectively incorporate it into the server, and the InnoDB plugin was introduced.  It provided 5.1 users the option of deploying a more advanced version of InnoDB, or using the more conservative built-in version baked into MySQL.  By the time the plugin reached GA status, though, Oracle had announced the acquisition of Sun (and MySQL), and things started to change.  The coordination between the InnoDB development team at Oracle and the MySQL development team increased once we were all “under one roof”.  The strategic directions of InnoDB and MySQL were aligned, and the results can be seen in the tremendous work done for MySQL 5.5 and 5.6.  In fact, the InnoDB plugin was removed …

• Reduced the amount of noise being sent from cron so that we would actually be looking at the e-mails we get.
  
• Set up Tokutek for our Datazilla program.
  
• Debugged and solved a problem with the Tokutek engineers because tokudb’s mysqld was not recognizing the –defaults-file option (it’s a MySQL quirk, –defaults-file has to be the first option).
  
• Cleaned up and fixed a bunch of MySQL ACLs on several servers.
  
• Debugged a problem where slow query logs were not being copied to a central location. The solution involves changing the script to have splay, ssh keys, and opening some network flows.
  
• Changed Nagios alerts so that dev/stage machines only page during the workday, not during …

This week we present the basics of MySQL FULLTEXT search. We talk about the myisam_ftdump utility in Ear Candy, and present an introduction to Sphinx in At the Movies.

Events
MySQL Connect will be held in San Francisco on Saturday September 29th and Sunday September 30th. The schedule is now online.

read more

Oh I love these things: http://techcrunch.com/2012/08/22/how-big-is-facebooks-data-2-5-billion-pieces-of-content-and-500-terabytes-ingested-every-day/

Every day there are 2.5B content items shares, and 2.7B "Like"s. I care less about GiGo content itself, but metadata, connections, relations are kept transactionally in a relational database. The above 2 use-cases generate 5.2B transactions on the database, and since there are only 86400 seconds a day, we get over 60000 write transactions per second on the database, from these 2 use-cases alone, not to mention all other use-cases, such as new profiles, emails, queries...

And what's the size of new data, on top of all the existing …

The servers I help manage have a lot of deadlocks, especially around a few central tables that are important to many business functions. The queries against them are complex, and they crunch a lot of data in some cases. As a result, we have long-running transactions that often deadlock against others, and there are even many short-running jobs that touch only a single row at a time that can’t get their work done sometimes.

I’ve often said that deadlocks are a fact of life in transactional systems. The application must be able to deal with the deadlocks. This is true, but it’s not the whole story. The work needs to be done, unless it’s user-triggered and the user gets frustrated and abandons what they’re trying to do. That’s not the case in the applications I use; if something fails, it will get retried until it succeeds, because work queues and doesn’t go away until it’s completed.

Depending on how long it takes for …

It is a common question: what is the lifespan of a persistent, pooled, cached, however-you-call-it PHP MySQL connection? What about CGI, FastCGI, web server module? The answer is always the same. Standard I/O file handles, including socket connections, are bound to processes. The lifespan of a persistent, pooled, cached, however-it-is-to-be-called-in-context-x connection is that of the PHP process. Depending on the web server deployment model, a PHP process handles one or multiple web requests. Read on only if puzzled.

A process

Do you have any colleguages around? Please, ask them for "APUX". In case of no reply, get a copy and study. To become a master PHP developer you will have to master todays frameworks (Zend Framework, Symfony, Dojo, …) and yesterdays. Yesterdays framework is still dominant. Yesterdays framework is your operating system. "APUX" stands for …