I have to confess I'm kind of a wannabe hacker. I think of myself as a developer, yet in practice I always end up being a customer facing person like a Sales Engineer, a Trainer or basically anything where you do more talking than coding. But there is this tiny little Drupal module, footnotes, that I'm actually the proud maintainer of for several years now.

read more

dbForge Studio for MySQL has the Database Designer functionality that allows you to build and view the structure of your database using the diagrams. You can read more about it in Getting Started with Database Designer article.

Database Designer also can save a database diagram as an image.

Saving Database Diagram as an image

To save database diagram as an image, perform the following steps:
1. Right-click on the diagram and select “Export to image…”.

Figure 1: Export to an Image

2. Choose one of the image formats to which you want to save your diagram.

…

We've been looking at high concurrency level issues with Drizzle and MySQL. Jay pointed me to this article on the concurrency issues due to shared cache lines and decided to run some of my own tests. The results were dramatic, and anyone who is writing multi-threaded code needs to be aware of current CPU cache line sizes and how to optimize around them.

I ran my tests on two 16-core Intel machines, one with a 64 byte cache line, and one with 128 byte cache line. First off, how did I find these values?

one:~$ cat /proc/cpuinfo | grep cache_alignment
cache_alignment : 64
...

two:~$ cat /proc/cpuinfo | grep cache_alignment
cache_alignment : 128
...

You will see one line for each CPU. If you are not familiar with /proc/cpuinfo, take a closer look at the full output. It's a nice …

A while ago Arjen Lentz blogged about transient MySQL errors that can occur when using a transactional storage engine, like say InnoDB.

Since I'm a fan of the reliability and automated recovery that InnoDB provides, I use it for all the Drupals that I host.  However, on a very busy site, this may lead to deadlocks. These in turn lead to users seeing errors, which is something I'd like to avoid. Especially if the error could be prevented.

What I've done to make use of these error codes is change the _db_query() function in includes/database.mysql.inc and wrap the call to mysql_query() in a loop.

The function now checks the returned error code and if the code indicates a transient error, it will try to rerun the query after sleeping for 50 milliseconds.  It will try each query up to three …

A while ago Arjen Lentz blogged about transient MySQL errors that can occur when using a transactional storage engine, like say InnoDB.

Since I'm a fan of the reliability and automated recovery that InnoDB provides, I use it for all the Drupals that I host.  However, on a very busy site, this may lead to deadlocks. These in turn lead to users seeing errors, which is something I'd like to avoid. Especially if the error could be prevented.

What I've done to make use of these error codes is change the _db_query() function in includes/database.mysql.inc and wrap the call to mysql_query() in a loop.

The function now checks the returned error code and if the code indicates a transient error, it will try to rerun the query after sleeping for 50 milliseconds.  It will try each query up to three …

Would you like to find out how to build a continuous ETL process integrating source systems, MySQL data warehouse, and Mondrian OLAP engine?

I'm going to be hosting a webinar tomorrow describing how to do this using SQLstream. (Basically a repeat of the webinar I gave at the MySQL conference this year, but many of you missed it.)

Join me and Damian Black, CEO of SQLstream, on the webinar at 11am PDT/2pm EDT tomorrow, Wednesday 27th May. To register for the webinar, visit https://www2.gotomeeting.com/register/668399275.

One of the cool things about talking about MySQL performance with ZFS is that there is not much tuning to be done Tuning with ZFS is considered evil, but a necessity at times. In this blog I will describe some of the tunings that you can apply to get better performance with ZFS as well as point out performance bugs which when fixed will nullify the need for some of these tunings.

For the impatient, here is the summary. See below for the reasoning behind these recommendations and some gotchas.

1. Match ZFS recordsize with Innodb page size (16KB for Innodb Datafiles, and 128KB for Innodb log files).
2. If you have a write heavy workload, use a Seperate ZFS Intent Log.
3. If your database working set size does not fit in memory, …

Solaris Cluster comes bundled with rich support for numerous software applications.

Follow the link to see a list of all the Solaris Cluster Agents available in the latest release of  Solaris Cluster  - SC 3.2 01/09.
For most of these applications the latest versions are supported.  In this blog I specifically want to highlight the latest support
for the SAP NetWeaver stack and highlight some key features provided by Solaris Cluster to make SAP highly available on
Solaris.

Solaris Cluster 3.2 HA SAP Web Application Server agents now support SAP 7.1 on S10 SPARC and X64. You will need
patch# 126062-06 or later for S10 SPARC or patch# 126063-07 or later for S10 X64. This patch is required for the following
Resource Types (RTs) - SUNW.sapenq, SUNW.saprepl, SUNW.sapscs, …

Since the Sun acquisition was announced I continue to get questions on how it will impact MySQL. This seems to be mainly as a result of the close affinity between PHP and MySQL. I must admit that while I had a lot of immediate thoughts when the IBM/Sun rumor was floating around, I have had a bit of a harder time figuring out what the Oracle/Sun acquisition means for the various pieces of Sun's business including MySQL.

Like many I believe that Oracle would not want to kill MySQL and that steering it more towards the SQL Server market as opposed to Oracle DB could make a lot of sense for Oracle. After all, MySQL definitely competes with SQL Server on ease-of-use and some of the mainstream relational DB features, while for the very high-end features, Oracle is still way ahead (Real Application Clusters, Database Resident Connection Pooling, Backup & …

If you missed Gearman or Drizzle at the MySQL Conference, have no fear, a number of folks will be at OSCON too! There will be a many opportunities to learn more or get involved with the two projects:

• 3-Hour Gearman Tutorial - Learn about the latest developments and participate in hands-on demos to help build your own Gearman-powered applications.
• 45-Minute Gearman Session - Get a more concise glimpse about what Gearman is and how to use it.
• 45-Minute Drizzle Panel - Get an update and ask questions about …