I've seen a few people link to an INFORMATION_SCHEMA query to be able to find any indexes that have low cardinality, in an effort to find out what indexes should be removed.  This method is flawed - here's the first reason why:

PLAIN TEXT SQL:

1. CREATE TABLE `sales` (
2. `id` int(11) NOT NULL AUTO_INCREMENT,
3. `customer_id` int(11) DEFAULT NULL,
4. `status` enum('archived','active') DEFAULT NULL,
5. PRIMARY KEY (`id`),
6. KEY `status` (`status`)
7. ) ENGINE=MyISAM AUTO_INCREMENT=65691 DEFAULT CHARSET=latin1;
8.  
9. mysql> SELECT count(*), STATUS FROM sales GROUP BY STATUS;
10. +----------+---------+
11. | count(*) | STATUS  |
12. +----------+---------+
13. |    65536 | archived |
…

Part 1 of our series set-up our "test"  application and looked at boosting performance of the application by buffer MySQL with memcached.  Our test application is simple and requires only 3 basic operations per transaction 2 reads and 1 write.  Using memcached combined with MySQL we ended up nearly getting a 10X performance boost from the application.  Now we are going to look at what we could achieve if we did not have to write to the database at all.  So let's look at what happens if we push everything including writes into memcached.

Wow that's shockingly fast isn't it! I guess being completely in memory helps for this app.  What is very interesting is accessing 100% of the data in memcached gives very similar numbers to accessing 100% of the data in memory in the DB ( part 1 …

Olio0.2 is comming

With IntelliJ now being available under an Open Source license, developers have another option to choose from when it comes to Java-based IDEs/Frameworks (Eclipse and NetBeans being the other two prominent ones). Choice is always good, and being an Open Source enthusiast, I of course welcome JetBrain's move!

However, as I'm not really a heavy GUI-based IDE user myself, I can't really comment on which one is the best. These kind of discussions tend to turn into a Holy War anyway... In the end it's likely that each of them gets the job done and you have to come to your own conclusions, based on your personal preference and requirements.

I personally would be interested in …

The GRAPH engine allows you to deal with hierarchies and graphs in a purely relational way. So, we can find all children of an item, path from an item to a root node, shortest path between two items, and so on, each with a simple basic query structure using standard SQL grammar.

The engine is implemented as a MySQL/MariaDB 5.1 plugin (we’re working on a 5.0 backport for some clients) and thus runs with an unmodified server.

Demo time! I’ll simplify/strip a little bit here for space reasons, but what’s here is plain cut/paste from a running server, no edits

-- insert a few entries with connections (and multiple paths)
insert into foo (origid, destid) values (1,2), (2,3), (2,4), (4,5), (3,6), (5,6);
-- a regular table to join on to
insert into people values (1,"pearce"),(2,"hunnicut"),(3,"potter"), …

Copies of the slides from the first two "Windows and MySQL" webinars are now available:

Part 1: Getting Started with MySQL on Windows
Part 2: MySQL for the SQL Server DBA

Also, if you missed Reggie Burnett's "MySQL and the ADO.NET Entity Framework" webinar a few weeks ago, his slides are also available here.

Yes, 150 means we added some 30 performance statistics to the MySQL native driver for PHP (mysqlnd) since monday. The new statistics are explained in three words: counting COM_* commands. COM_* commands refers to the command packets of the MySQL client server protocol. For example, COM_QUERY is used to execute nonprepared SQL statements.

Please check the earlier blog postings on how to use and access the statistics: PHP: 59 tuning screws for mysqlnd, PHP: 120 tuning screws for mysqlnd. The information given in those articles will find its way into the PHP and MySQL manual. The MySQL documentation team is working on an …

Yes, 150 means we added some 30 performance statistics to the MySQL native driver for PHP (mysqlnd) since monday. The new statistics are explained in three words: counting COM_* commands. COM_* commands refers to the command packets of the MySQL client server protocol. For example, COM_QUERY is used to execute nonprepared SQL statements.

Please check the earlier blog postings on how to use and access the statistics: PHP: 59 tuning screws for mysqlnd, PHP: 120 tuning screws for mysqlnd. The information given in those articles will find its way into the PHP and MySQL manual. The MySQL documentation team is working on an …

As one of the world’s leading eCommerce Service Providers, Shopatron needed to further improve scalability and availability of their eCommerce services to keep pace with their rapidly growing business, while at the same time, reducing costs.

After extensive evaluations, Shopatron selected MySQL Cluster to power its back-end database, running the entire eCommerce fulfillment engine.

Since deploying MySQL Cluster, Shopatron have achieved:

• continuous service availability with sub-second failover and fully automated recovery
• real-time performance, reducing query times from 3 seconds to 2 milliseconds
• extreme levels of scalability on commodity hardware and open source software
• reduced licensing, support and operational management costs

Tune into this webinar where Shopatron’s CIO/COO and VP of Engineering will both share their experiences and best practices of …

As network use grows and services become more dynamic, so existing Authentication, Authorization and Accounting (AAA) environments can struggle to keep pace with demand.

Tune into this webinar where you can hear from the Alan Dekok, one of the founders of the FreeRADIUS project and CEO of Network RADIUS, discuss the concepts and implementation of RADIUS services using the FreeRADIUS server and the MySQL Cluster database to deliver highly available and scalable AAA services.

As always, this webinar is free and you can register here. I will be manning the Q&A during the webinar.

In this session, you will learn about:

• potential AAA limitations as network environments grow
• advantages of deploying FreeRADIUS with MySQL Cluster
• Performance, sizing and deployment of an AAA environment using …