The brief outage was due to a scheduled move of the servers to a separate rack and subnet dedicated to our work with the Center for Information Assurance & Cybersecurity (ciac) at the University of Washington Bothell (uwb), and a11y.com

I am currently exercising the new (to us) equipment and hope to winnow the less than awesome equipment over the next quarter. I spent the last six months finding the best in breed of the surplussed DL385 and DL380 chassis we (work) were going to have recycled. The team and I were able to find enough equipment to bring up one of each with eight and six gigs of memory, respectively. These will make excellent hypervisors for provisioning embedded instances of Slackware, Fedora, RHEL, CentOS, Debian, FreeBSD, OpenSolaris, OpenIndiana, FreeDOS, etc.

When I initially configured this xen paravirt environment, I failed to plan for integration with libvirt, so I am now re-jiggering the software bridges so …

In this blog we discuss invalid dates in MySQL, how to retrieve them using Connector/Python and we raise the question: Should Connector/Python raise an error or just keep returning None on invalid dates?

If you run MySQL without proper SQL Modes, you will be able to update and
read invalid dates such as ’2012-06-00′. If you’ve payed attention the past decade, you’ll know that you can prevent this configuring your MySQL server setting SQL Mode to ‘TRADITIONAL’.

Now, the problem if this is allowed, how do we get invalid dates using MySQL Connector/Python?

Lets look at an example inserting an invalid date and trying to read it again using MySQL Connector/Python:

>>> cur = …

A special extended edition of Tech Messages for 2011-09-21 through 2012-05-11:

• Understanding Linux CPU Load - when should you be worried?
• Performance Testing - Load Balancer SSL Stress Testing
  This is a great simple test. Thanks, Corey!
• Mosh: the mobile shell
• Twitter open sources its MySQL secret sauce
• Lab Overview
  This guy is serious about his lab!

The new MySQL 5.6 Development Milestone Release (DMR) includes many new enhancements. One of the most impressive is the use of Global Transaction Identifiers (GTIDs) for replication. With GTIDs enabled, administrators no longer need to keep track of binary log files and positions. In a nutshell, GTIDs simplify the setup and maintenance of replication.

MySQL Utilities has taken this a step further by providing two new utilities that automate two of the most complex replication administration tasks - switchover and failover. Switchover is changing the role of an active, healthy master to one of its slaves whereas failover is the act of promoting a candidate slave to become the new master. Clearly, switchover is an elective operation and failover is performed when there are issues with the master.

The GTID utilities are included in release-1.0.5 of MySQL Utilities. They are included as a plugin for MySQL Workbench or via …

We have moved bugs for MySQL Connector/Python from Launchpad to the MySQL Bugs website http://bugs.mysql.com. Reports which are (probably) fixed in newer code were not taken with. If there is a bug which you really want to get tracked: please report it again.

Please use the MySQL Bugs website to report problems using MySQL Connector/Python. To see a list of active reports, click here.

…

Splitmytab.net is finally for the public to check out. Splitmytab is a bill splitting and IOU system for friends. It uses facebook’s login, so you won’t need to put in anyone’s emails, names, or get people to sign up for an account.

It’ll automatically keep balances of who owes who, so you can keep a running tab with friends and always know who’s buying the next case of beer.

Please note: I’m not a designer, so there’s a few rough corners, but what’s there is simple and it works.

Tech Notes:

• Backend is MySQL 5.5
• Written in Python
• Nginx with tornado
• Redis used on occasion
• Originally was writing pure JS then switched to Coffeescript

Enjoy, and please leave feedback!

In a previous post, I demonstrated a simple Python database API with a syntax similar to jQuery. The goal was to provide a simple API that would allow Python programmers to use a database without having to resort to SQL, nor having to use any of the good, but quite heavy, ORM implementations that exist. The code was just an experimental implementation, and I was considering putting it up on Launchpad.
I did some basic cleaning of the code, turned it into a Python package, and pushed it to Launchpad. I also added some minor changes, such as introducing a define function to define new tables instead of automatically creating one when an insert was executed. Automatically constructing a table from values seems neat, but in reality it is quite difficult to ensure …

We’ve seen the rise of open source software in the enterprise and also beyond the IT industry, but the real keys to openness and its advantages in today’s technology world — where efficient use of cloud computing and supporting services are paramount — exist in open application programming interfaces, or APIs.

Open source software continues to be a critical part of software development, systems administration, IT operations and more, but much of the action in leveraging modern cloud computing and services-based infrastructures centers on APIs. Open APIs are the new open source.

Read the full story at LinuxInsider.

I recently found Todd's posts on interceptors which allow callbacks (called interceptors) to be registered with the connector so that you can intercept a statement execution, commit, or any of the many extension points supported by Connector/Java. This is a language feature that allow you to implement a number of new features without having to change the application code such as load-balancing policies, profiling queries or transactions, or debugging an application.

Since Python is a dynamic language, it is easy to add interceptors to any …

There have been some request to have some reconnect possibilities in Connector/Python. I’m wondering now whether there should be some automatic reconnect on certain errors within the database driver.

My personal feeling is to have no automatic reconnect within Connector/Python and the programmer has to come up with retrying transactions herself.

For example:

        cnx.disconnect() # For testing..
        tries = 2
        while tries > 0:
                tries -= 1
                try:
                        cursor.execute("INSERT INTO t1 (c1) VALUES ('ham')")
                        cnx.commit()
                except mysql.connector.InterfaceError:
                        if tries == 0:
                                print "Failed inserting data after retrying"
                                break
                        else:
                                print …