Contemporary software engineering models include many loosely-defined layers. Database developers might help with other layers, but for the most part a database administrator’s domain is the persistence layer.

• 
  
• Presentation
  
• Application
  
• Business Logic
  
• Persistence (also called Storage)
  

The Daily WTF has an article on The Mythical Business Layer makes the case for not separating the business layer and the application layer:

A good system (as in, one that’s maintainable by other people) has no choice but to duplicate, triplicate, or even-more-licate business logic. If Account_Number is a seven-digit required field, it should be declared as CHAR(7) NOT NULL in the database and …

Update: Karanbir says “Just one thing to keep in mind is that we dont want too many people using it from the Testing repository - we only need enough feedback to move it from testing to stable ( and to be honest, there are already 8 people who have said yes it works - so move to stable should happen within the next 24 - 48 hrs ). Once the package is in stable, users on CentOS4 and 5 wont need to do anything more than just ‘yum install maatkit’ and it will install for them.”

At least one person (Karanbir Singh) is working to get Maatkit into the CentOS repositories, and I believe there might be movement towards RHEL also. From an email to the Maatkit discussion list a little while ago,

I am in the process of getting maatkit into the CentOS-Extras …

When we write about investors on this blog we are normally referring to angel and VC investors and the funding they provide to open source start-ups. There is a small, but growing, list of VCs that clearly understand the open source development and distribution models and the long-term profit potential of open source software vendors.

Can the same be said of individual and institutional investors buying and selling shares in publicly traded software companies? Not according to the analysis of Oliver Alexy, a research assistant and doctoral candidate at the Technische Universität München TUM Business School in Munich, Germany.

Oliver has analyzed the impact that releasing software under open source licenses has on a company’s share price. Details have been published this week in the …

Running MySQL 4 And MySQL 5 Concurrently

This tutorial shows how to install MySQL 5 on a system where MySQL 4 is already running. It also shows how to configure phpMyAdmin to use both databases.

I was poking around the MySQL Worklog again over the weekend, and found a request for materialized views for MySQL. This feature has existed in Oracle for a while, in DB2 as a materialized query table, and appeared in MS SQL Server 2000 and 2005 as indexed views.

What is a materialized view?

A materialized view is a database object that contains the results of a query. The FROM clause of the query can name tables, views, and other materialized views. (from Oracle).

Essentially a materialized view …

Well, the first summary of last 10 variable day outs.

Day Outs:

• Day Out #1: delay_key_write
• Day Out #2: key_buffer_size
• Day Out #3: max_connect_errors
• Day Out #4: innodb_buffer_pool_size
• Day Out #5: innodb_thread_concurrency
• Day Out #6: …

If you’re an advanced MySQL person, you might already know these, in which case, please read anyway, because I still have some questions. On the other hand, f you’re someone who launched an application without a lot of database background, thinking “MySQL Just Works”, you’ll eventually figure out that it doesn’t, and in that case, maybe these tips will be of some use. Note that I’m speaking specifically about InnoDB and MyISAM, since this is where most of my experience is. Feel free to add more to this content in the comment area. 

InnoDB vs. MyISAM

Which one to use really depends on the application, how you’re deploying MySQL, your plans for growth, and several other things. The very high-level general rule you’ll see touted on the internet is “lots of reads, use MyISAM; lots of writes, use InnoDB”, but this is really an oversimplification. Know your application, and know your data.  If all of …

Oursql-conferences is a discussion list for a community conf, not to compete with but augmenting the Sun/MySQL one. We're here to discuss such an event, its potential, dates/location, and get it going!

It's a public group, please blog & tell others about it!
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By Eric Day - May 6 - 4 authors - 5 replies

Would a Virtual Conference Work?
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How about a community build?
By Arjen Lentz - Apr 27 - 6 authors - 6 replies

Creation of oursql-sources Group
By Mark Schoonover - Apr 25 - 1 author - 0 replies

What about MySQL Camp?
By Keith Murphy - Apr 25 - 2 …

Oursql-conferences is a discussion list for a community conf, not to compete with but augmenting the Sun/MySQL one. We're here to discuss such an event, its potential, dates/location, and get it going!

It's a public group, please blog & tell others about it!
Sheeri suggested OurSQL, like her podcast.

Members: 91

Discussions:

Conference Outline
By Eric Day - May 6 - 4 authors - 5 replies

Would a Virtual Conference Work?
By Sheeri K. Cabral - Apr 29 - 7 authors - 11 replies

How about a community build?
By Arjen Lentz - Apr 27 - 6 authors - 6 replies

Creation of oursql-sources Group
By Mark Schoonover - Apr 25 - 1 author - 0 replies

What about MySQL Camp?
By Keith Murphy - Apr 25 - 2 …

Oursql-sources email group was created to discuss community MySQL builds, patches and adding features using the GPL'd version of MySQL sourcecode.

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Discussions:

The MySQL CLA - A barrier to community contributions?
Source trees, Public Development and Builds - Version control, community contributions.

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