I learn more and more about Galera every day.  As I learn more, I try to keep my myq_gadgets toolkit up to date with what I consider is important to keep any eye on on a PXC node.  In that spirit, I just today pushed some changes to the ‘wsrep’ report, and I thought I’d go over some of the status variables and metrics being tracked there with the aim to show folks what they should be watching (at least from my opinion, this is subject to change!).

First, let’s take a look at the output:

[root@node3 ~]# myq_status -t 1 wsrep
Wsrep    Cluster        Node           Queue   Ops     Bytes     Flow        Conflct
    time  name P cnf  #  name  cmt sta  Up  Dn  Up  Dn   Up   Dn pau snt dst lcf bfa
19:17:01 trime P   3  3 node3 …

If you are a database developer who wants to create applications using MySQL, then the MySQL for Developers course is for you. This course covers how to plan, design and implement applications using the MySQL database with realistic examples in Java and PHP.

To see more details of the content of the MySQL for Developers course, go to http://oracle.com/education/mysql and click on the Learning Paths tab and select the MySQL Developer path.

You can take this course as a:

• Live-Virtual Event: Follow this live instructor-led event from your own desk - no travel required. Choose from a selection of events on the calendar in languages such as English, German and Korean.
• In-Class Event: Travel to an education center to take this class. Below is a sample of events on the schedule.

I’ve had many dealings with SK Planet, in South Korea, so when they asked me to speak at their inaugural Tech Planet, I jumped at the opportunity. I was already pre-given a topic titled “NewSQL”, so I talked about the evolution of SQL -> Big Data -> NoSQL -> NewSQL, all thanks to papers written by Google research, and then focused on how MySQL & MariaDB is gaining many new interfaces: mariasql, HandlerSocket, dynamic columns, memcached InnoDB plugin, …

Subversion also more famouly know as SVN is a version management tool used to manage source code, documents, designs, etc.. in software develpment. SVN is a centralized version control system where the main repository resides in a centralized environment and the parties involved in a project can download a copy of the repository to their […]

Last week we had our first Swedish MySQL User Meeting "SMUG" in Stockholm. The event was at Oracle engineering office at Söder and 20 users attended this first event!

I presented a talk on news from MySQL connect, it was a blend of MySQL 5.6 RC and MySQL Cluster 7.3DM, you can see slides on slideshare

Look out for our next SMUG event ;)

Time for another poll! I wonder What CPU Architecture do you use for running MySQL in Production ? I guess most of the game here is between Intel and AMD x86-64 variants though I wonder if there is still a lot of use for others in the wild. If I am missing some Architecture which is still alive in your data center please post a comment and I will add it to the list.
Please select all what applies. If you would like to share what works better for you in the comments I appreciate it.

Note: There is a poll embedded within this post, please visit the site to participate in this post's poll.

Earlier this week, Cédric blogged about how easy we can get confused between a covering index and a full index scan in the EXPLAIN output. While a covering index (seen with EXPLAIN as Extra: Using index) is a very interesting performance optimization, a full index scan (type: index) is according to the documentation the 2nd worst possible execution plan after a full table scan.
If it is obvious that a full table scan is not good for performance, how much can we expect if we can switch to a full index scan? In other terms, is a full table scan always the worst possible execution and should it be avoided at all costs?

Let’s take the employees database, and slightly modify the employees tables:

mysql> ALTER TABLE employees ADD INDEX idx_first (first_name),ENGINE=InnoDB;

One of the students wanted an equivalent example to an Oracle DML trigger sample that replaces a white space in a last name with a dash for an INSERT statement. Apparently, the MySQL trigger example in the Oracle Database 11g and MySQL 5.6 Developer Handbook was a bit long. I have to agree with that because the MySQL DML trigger demonstrated cursors and loops in the trigger code.

Triggers can be statement- or row-level actions. Although some databases let you define statement-level triggers, MySQL doesn’t support them. MySQL only supports row-level triggers. Row-level triggers support critical or non-critical behaviors. Critical behavior means the trigger observes an insert, update, or delete that must be stopped, which means it …

This week’s Log Buffer #296 focuses on Oracle, SQL, and MySQL weblogs from across the planet. Log Buffer Editions are the manifestation of the fact that nerd bloggers from databases are not only growing but they are also producing immense volume of quality ramblings. Enjoy. Oracle: Stelios Charalambides book on SQLTXPLAIN is now announced, Carlos...

One of my favorite tools in the Percona Toolkit is pt-query-digest.  This tool is indispensable for identifying your top SQL queries, and analyzing which queries are accounting for your database load.

But the report you get from pt-query-digest is only as good as the log of queries you give it as input.  You need a large enough sample of query logs, collected over a period of time when you have representative traffic on your database.

You also need the log to include all the queries, not just those that take more than N seconds.  The reason is that some queries are individually quick, and would not be logged if you set the long_query_time configuration variable to 1 or more seconds. …