I’ve been working, on and off, for the past few months on a solution that really pulls together most of the major functions of our platform into an entire solution.  The SQR uses a little bit of the entire Pentaho Platform including Action Sequences, Kettle ETL, database structure initialization, Mondrian OLAP definitions, summary tables, JFreeReports, Pentaho Analysis views, user prompting, custom report rollups in Excel, etc.  It looks, feels, and operates as an entire solution, soup to nuts, running on Pentaho.

The SQR doesn’t aim to replace reports provided with Bugzilla.  Bugzilla is a good database schema for running an application (ie, Bugzilla) but it’s sometimes difficult if not impossible to ask some important analytic questions.  Questions such as:

and “Open vs Closed with a trend over time”

and the ability to build some of your own dashboards

The …

MySQL Connector/Net 5.0.1 Beta has been released. MySQL Connector/Net is an all-managed ADO.Net provider for MySQL. While this release is suitable for any version of MySQL, it is strongly encouraged that this release not be used on any production data. This release is feature complete with the exception of DTC support in System.Transactions.

It is now available in source and binary form from the Connector/Net download pages at http://dev.mysql.com/downloads/connector/net/5.0.html and mirror sites (note that not all mirror sites may be up to date at this point of time - if you can't find this version on some mirror, please try again later or choose another download site.)

Highlights in this release:

Support for ADO.Net 2.0 interfaces and subclasses
(this release now includes foreign key support)

…

bit, bitwise operators, boolean performance

Boston October MySQL User Group: see full event listings at:

http://mysql.meetup.com/137/calendar/5118339/

Tuesday, Oct. 10th at MIT, free pizza and soda (thanks to MySQL, AB and the MIT community). Please RSVP!!

To RSVP anonymously, please login to the Meetup site with the e-mail address “admin at sheeri dot com” and the password “guest”.

Plenty of free parking (you can park in MIT lots after 3 pm); 1 block south of the Kendall Square T stop.

————–

Most of …

If you are used to open source products, chances are you have gone through this routine more than once. Search for what you need, find a suitable product, go to its web site, download it, test it. Then, if you like it, you start using it right away, otherwise you dump it without a second thought.
The whole process takes less than one minute for small packages. But anyway, even for larger packages, the total time that this whole business requires your attention is very low. Even if it requires a huge download, it can be left unattended and you can resume the testing task when you feel like it. The bottom line is that we got used to a quick try-and-use process of open source products.

Sometimes, though, while performing the above routine, there is a unexpected obstacle. The product maker requires a free login. You don't have to pay anything, but you have to go through the motions of filling a form that asks you everything about …

This is just a hypothesis at this point, but my experience with Lineo, Novell, Alfresco, and the companies I advise is pushing me toward the following:

An open source company's sales model should be "low-touch" until the point that companies are buying your product more for its intrinsic qualities than because it's cheap/open source.I need to figure out a more concise way of saying that, but wanted to get it up on the web so that others could see if it matches up with their experience.

The thought behind that statement is this: When companies are willing to pay parity or a premium for your product, it means they're no longer primarily interested in you because you're open source. Some companies will download your product solely because it's open source. They may initially be interested because they think they want an open source widget, and your product fits that bill. For such interest, a low-touch, inside sales approach is …

Saturday was a great time. I really enjoyed giving the session on performance tuning and talking to (so many!) developers and DBAs. My best guess were about 160 or more folks were there, which is a great turnout. Anyway, as I promised in the session, below are the slide decks for the session I gave, along with the longer one from OSCON (entitled "Maximum Velocity MySQL") and the seminar on tag schemas. Cheers!

• Performance Tuning Best Practices
• Maximum Velocity MySQL
  • And the two demo SQL queries...
  • selectivity_correlated.sql
  • …

Today I spent several hours trying to find a problem in our application until I found out there was a problem on the MySQL side. In our setup we have several slave machines that replicate data from a master server. The slaves are configured with a series of replicate-do-table directives in the my.cnf file so that only parts of the schema get replicated. The remaining tables are modified locally, so to avoid conflicts they are not updated with data coming from the master.

We do however have the need to replicate data from the master for some special-case tables. To solve this we usually have a column that indicates whether a record was created on a master or a slave machine and use an appropriate WHERE clause in all updates. This avoids collisions in concurrent INSERTs on the master and the slave. The application knows which of the two records to use.

Due to historical reasons I …

If you’re a frequent reader, you might have noticed that I’m on a roll contributing MySQL patches by now… there are many more to come. This is part of the reason that I founded Proven Scaling — to be able to spend my time solving interesting problems and making MySQL better. So what about triggers, stored procedures, and call stacks?

I’ve written a patch that implements three new functions in MySQL 5.01:

• CALLER(level) — Returns the SQL statement in the call stack at level, where 0 is the level containing the call to CALLER() itself (which is nearly useless), and 1 and above are any stored procedure or trigger calls that got us here.
• CALLER_DEPTH() — Returns the current depth of the call stack, not counting 0. …

I've made more improvements to the duplicate index checker. I addressed a MySQL bug Roland Bouman mentioned to me, added more tests to the suite, and made changes so it considers more types of indexes now (HASH, BTREE, SPATIAL). I made no changes to the foreign key checking.