The MySQL client has some functionalities some of us never use. Why would you use them and what is the added value of this?

Every DBA and developer has had a moment when he or she needs to connect to a MySQL database using the command line tool. Therefore I’ve written down an explanation of some command line commands you can insert in the CLI, most of them give added value and make your experience with the cli more enjoyable.

prompt

Who has never witnessed the scary feeling of not being connected to the write database when having several terminals open. I do, due to the fact I use the prompt functionality.

mysql >\R Production >
PROMPT set to 'Production > '

Or you can go a bit further and visualise the user, host and active database in:

mysql > \R \u@\h [\d]>
PROMPT set to '\u@\h [\d]>'
root@testbox [test]>

edit

In some …

Data migrations always have a wide range of challenges. I recently took on a request to determine the difficulty of converting an ecommerce shop's MySQL 5.0 database to PostgreSQL 9.3, with the first (presumably "easier") step being just getting the schema converted and data imported before tackling the more challenging aspect of doing a full assessment of the site's query base to re-write the large number of custom queries that leverage MySQL-specific language elements into their PostgreSQL counterparts.

During the course of this first part, which had contained a number of difficulties I had anticipated, I hit one that I definitely had not anticipated:

ERROR:  value too long for type character varying(20)

Surely, the error message is absolutely clear, but how could this possibly be? The obvious answer--that the varchar definitions were different lengths between MySQL and PostgreSQL--was sadly quite wrong (which you knew, …

In Part I of this blog series we installed and configured our MySQL Fabric, now we are ready to start test our python application against MySQL Fabric.

Most of this is covered in first blog but lets do a short recap. We now have a HA-group consisting of 3 MySQL servers, these are running on ports 63307 - 63309. We have also configured one MySQL instance 63306 to act as backing store for MySQL Fabric, that is holding all fabric meta data for us.

Now it time to …

While working on a recent support issue as a Percona Support Engineer,  I got one question from a customer asking how to monitor ALTER TABLE progress. Actually, for MySQL 5.5 and prior versions, it’s quite difficult to ALTER the table in a running production environment especially for large tables (with millions records). Because it will rebuild and lock the table affecting the performance as well as our users. Therefore even if we start ALTER it’s really important to know when it will finish. Even while creating the index, ALTER TABLE will not rebuild the table if fast_index_creation is ON but still it might lock the table.

…

Dr. Adrian Partl is working in the E-Science group of the Leibniz Institute for Astrophysics Potsdam (AIP), where the key topics are cosmic magnetic fields and extragalactic, astrophysics is the branch of astronomy concerned with objects outside our own Milky Way galaxy
Why did you decided to create a Job Queue plugin, what issues does it solve?
A: Basically our MySQL databases hold astronomic simulations and observations content, the datasets are in multi Terra Bytes size and queries can take long time, astronomers can definitely wait for data acquisition, but jump on the data as soon as they are available.  Job Queue offer a protection from too many parallel query executions and prevent our servers to be spammed. Multiple queues are here to give us priority between users, today queries are executed as soon as a slot is available. Some timeouts per group can be define and queries will be killed passing that delay. …

Often I would need to work on customer servers where MySQL Utilities would be a really good fit for the tools I need. However, I would not want to mess around with the customer servers just to have it running so I would have the tools built and sandboxed on its own directory where I can cleanup later. Here’s how:

cd ~
wget http://mysql.mirrors.hoobly.com/Downloads/MySQLGUITools/mysql-utilities-1.4.1.tar.gz
tar xzf mysql-utilities-1.4.1.tar.gz
cd mysql-utilities-1.4.1
python setup.py build
python setup.py install --root=/home/revin/mysql-utilities-1.4.1
export PYTHONPATH=.:/home/revin/mysql-utilities-1.4.1/usr/lib/python2.6/site-packages
/home/revin/mysql-utilities-1.4.1/usr/bin/mysqlfrm --help

Your source of the package and install directory may vary – enjoy!

Sometimes people’s perspective can be so interesting. I mean this with absolutely no irony. Josh Berkus wrote recently in a post about upcoming JSON improvements in PostgreSQL 9.4:

MySQL largely rose on the success of PHP, and it fell as PHP became marginalized.

This is an aside in the blog post, off-topic. But it’s interesting to discuss because it reveals the completely different things people see when they look at something. It’s like the proverbial story about the blind men describing an elephant. We have such a variety of perceptions.

This post, by the way, is not yet another flame war about MySQL versus PostgreSQL. To the contrary, it is very important for MySQL users and community members to understand that there are other communities who do not share the same assumptions, values, and beliefs at all. In …

As mentioned in my recent MySQL Performance Blog interview, Oracle has a number of vacancies in the MySQL team. By my count, there are 21 current vacancies:

• IRC2431754
  Software Developer 4
  MySQL Server Development (Windows)
• IRC2433642
  Software Developer 4
  MySQL Server Development (Replication)
• IRC2435607
  Internet Sales Representative II
  MySQL Corporate Sales
• IRC2437590
  Software Developer 3
  MySQL Enterprise Tools
• IRC2423566
  Technology Sales Representative III
  MySQL Sales
• IRC2421573
  Technical Analyst 3-Support
  MySQL Support
• IRC2409719
  Sales Consultant
  MySQL Global Business Unit
…

How do you get data from a MySQL Cluster into Hadoop? Easy, replicate from the cluster to a stand alone MySQL instance and from there use the MySQL Hadoop Applier to HDFS.

This question came from a long time MySQL user who has jumped into the Big Data world.

The MariaDB developers have made several releases in the past week. Rather than post about all of them separately, we decided to combine them into one post. Details for each release are available on their individual Release Notes and Changelog pages.

MariaDB 5.5.36

First up is MariaDB 5.5.36. This is a Stable (GA) release. Apart from general maintenance, bug fixes, and updates, TokuDB is now included in RPM packages for CentOS 6 on x86-64.

Download MariaDB 5.5.36

Release Notes Changelog …