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At the recent New York PHP Group in New York, I gave a presentation on “Secrets of mysqlnd”. While there are no real “secrets” of the new MySQL Native Driver for PHP, available in PHP 5.3, and the default for PHP 5.4+ replacing libmysqlclient, there are new features of the driver many are unaware of. If you have ever had to fight the gods with compiling a particular version of PHP with the right libmysqlclient dependency, the good news is that legacy requirement is no longer necessary.

Some of the topics discussed in detail included support for read/write splitting and load balancing with existing applications, …

I’m sure that many of you use the magic query from Shlomi.
This query retrieves the difference between two status values with a single query.
I’m really fan of this kind of query and about this query in particular. This query is very useful to retrieve an information without to have to store a middle result.

Now, I tried this query on a MariaDB 5.5 server and I had a surprise :

The result was a bit strange, with negative or null values.

I’ve just had these server for few hours in my hands and I had no more time to analyze the situation.
I assume that the subquery optimisations in MariaDB can be involve here but it’s just an assumption.

Does anyone encountered the …

Intro
While working on one of the MySQL to Oracle replication projects for Continuent, I needed to implement an open-source utility for transforming MySQL schema to an Oracle dialect (DDL statements that create specific schema on Oracle) to save from otherwise tedious work. This article introduces ./ddlscan tool, which does that and is extensible to do much more.

Ingredients
Here's what you'll need:

• Your favorite DBMS with some tables. Currently supported MySQL, Oracle and PostgreSQL.
• Latest Tungsten Replicator build. Not even needed to install, enough to untar.
• Velocity template of your choice. You will find …

The MySQL optimizer makes the decision of what execution plan to use based on the information provided by the storage engines. That information is not accurate in some engines like InnoDB and they are based in statistics calculations therefore sometimes some tune is needed. In InnoDB these statistics are calculated automatically, check the following blog post for more information:

http://www.mysqlperformanceblog.com/2011/10/06/when-does-innodb-update-table-statistics-and-when-it-can-bite/

There are some variables to tune how that statistics are calculated but we need to wait until the gathering process triggers again to see if there is any improvement. Usually …

Jet Profiler is a great MySQL  profiler. As the world of operating systems is getting more and more mixed, Jet Profiler offers a huge advantage: It is a Java based application and therefore able to run on Windows, Max OS X as well as on Linux.

Most of the time Java based applications tend to be very slow, however Jet Profiler shows that Java based applications can be fast and responsive as well. Even after hours of recording the UI stays responsive. To give you a working example, I had it recording on a server and real world load.

A nice feature of Jet Profiler is the setting for the polling interval. If you have a very, very busy server the polls could interfere with …

Jet Profiler is a great MySQL  profiler. As the world of operating systems is getting more and more mixed, Jet Profiler offers a huge advantage. It is a Java based application and therefore able to run on Windows, Max OS X as well as on Linux.

Most of the time Java based applications tend to be very slow, however Jet Profiler shows that Java based applications can be fast and responsive as well. Even after hours of recording the UI stays responsive. To give you a working example, I had it recording on a server and real world load.

A nice feature of Jet Profiler is the setting for the polling interval. If you have a very, very busy server the polls could interfere with the performance, so you can define the polling interval, which I did. However, instead of starting with a very slow polling interval, I …

EDIT: Video from today’s #DBHangOps!

Hey there peeps!

February 27th at 12:00pm PST it is! Check back here for more info and keep a watchful eye on the twitter search (and feel free to join the conversation!). The topics we’re looking to cover this week are:

• Day-to-day pain points (what takes more time than it should?)
  • rolling restarts and upgrades
  • Performing checksums on your data
    $ /usr/bin/pt-table-checksum \
--quiet \
--ignore-databases=mysql,percona,information_schema,per
formance_schema \
--lock-wait-time=50 \
--chunk-size-limit=0 \
--no-check-plan \
--no-check-binlog-format \
--max-lag=1 \
--replicate percona.checksums \
…

I’ve never been a very big fan of MyISAM; I would argue that in most situations, any possible advantages to using MyISAM are far outweighed by the potential disadvantages and the strengths of InnoDB. However, up until MySQL 5.6, MyISAM was the only storage engine with support for full-text search (FTS). And I’ve encountered many customers for whom the prudent move would be a migration to InnoDB, but due to their use of MyISAM FTS, the idea of a complete or partial migration was, for one reason or another, an impractical solution. So, when FTS for InnoDB was first announced, I thought this might end up being the magic bullet that would help these sorts of customers realize all of the benefits that have been engineered into InnoDB over the past few years and still keep their FTS capability without having to make any significant code changes.

Unfortunately, I think that hope may be premature. While it is true that InnoDB FTS in MySQL 5.6 is …

Canonical has just announced that the Ubuntu Developer Summit will no longer be face to face and every six months. Instead it will be entirely online and virtual, using Google Hangouts. (Here is the announcement.)

On the surface, this seems like a good idea: It's cheaper monetarily, it appears to open things up to people who are unable to travel, and it makes it easier to make complete records.

However, I think it's a bad idea, for several interrelated reasons.

Some decision making needs face-time to happen. For whatever reasons, internet-only communication is not enough for a good enough "meeting of the minds" for sticky or subtle engineering and design decisionmaking.

The IETF, who probably have the longest history of any organization ever of online internet-enabled …

Don’t forget to Register for the March 12 Virtual Developers Day. Two training tracks — one for beginners and the second is a MySQL 5.6 deep dive. The event will repeat on March 19th for Europe, Middle East, Africa, and some Asian Countries.