This entry is a follow up to TOTD #95 and shows how to use the recent integrations of JSR 299 in GlassFish v3 to convert a JSF managed bean to a JSR 299 bean (aka Web Beans). The TOTD #95 describes a simple Java EE 6 web application that uses Java Server Faces 2.0 components for displaying the results of a database query conducted by EJB 3.1 and JPA 2.0 classes.

The EJB class, which …

We’re looking to hire a Senior MySQL DBA over at Spinn3r.

You should obviously have MySQL experience. Love SQL, hate data corruption and slow queries, and preferably live in San Francisco.

Linux experience would be nice as well but not required.

Extra points if you are excited about SSD, *huge* amounts of data, have hacked on Drizzle or XtraDB

Spinn3r is a GREAT place to work. We’re growing fast and have cool new offices in SOMA.

…

Sometimes we have a lots of small and rather fast queries which use group by/order by, thus creating temporary tables. Some of those queries are retrieving text fields and mysql have to use disk (myisam) temporary tables. Those queries usually run for less than 1-2 seconds, so they did not get into slow query log, however, they sometimes add serious load on the system.

Here is the stat example:

bash-3.00$  /usr/local/mysql/bin/mysqladmin -uroot -p -i 2 -r extended-status|grep tmp_disk
...
| Created_tmp_disk_tables           | 109           |
| Created_tmp_disk_tables           | 101           |
| Created_tmp_disk_tables           | 122           |
...

40-50 tmp_disk_tables created per second

So, how can we grab those queries? Usually we have to temporary enable general log, filter out queries with “group by/order by” and profile them all. On solaris/mac we can use dtrace instead.

Here is the simple script, …

I recently started in a new company where a database does not have any data dictionary at all. I'm now doing a brute force work where I am trying to create my own data dictionary but I was wondering what are your strategies in learning the data inside a database?

Last week I've participated in several Performance Conferences and Trainings in Kiev. Events mainly were dedicated to the latest improvements within MySQL performance, as well Solaris and Oracle tuning / performance analyzing and best practices. The week was very hot :-) but I've enjoyed every day discussing with creative and smart people! People hungry on knowledge and ready to stay 2 hours more overnight outpassing all allowed timing - it was a real pleasure to share all I know! :-))

So, I'd like to thank all participants! As well Sun@Kiev and i-Klass teams who organized and prepared all these events! I may only wish to see such events more and more often, and don't forget to invite me again! :-))

NOTE : similar conference about MySQL performance improvement will be organized soon in Paris - so if you're …

Welcome to the 164th edition of Log Buffer, the weekly review of database blogs.

SQL Server

We have a delicious assortment of technical posts from the SQL Server world this week.

Piotr Rodak writes, “While I always knew and imagined that ON DELETE CASCADE may be useful, I wondered, what scenarios would be suitable for ON UPDATE CASCADE. I still don’t have this answer, but I came across some interesting behavior which kept me occupied for quite a bit more time that I had intended to.”

On In Recovery…, Paul S. Randall pursued the answers to …

I spoke at EdUIConf 2009, a new conference in my hometown of Charlottesville, Virginia. My presentation was on web interface performance; it's basically a twist on front-end performance in general. I slanted the talk towards web developers, rather than assuming the audience has full control over their Apache configuration.

The conference was relatively short -- two days. The first day was full-day sessions. I skipped from Molly's session on emerging web standards (good; summary of what I witnessed: HTML5 cometh) to Dan's session on visual design, which was excellent. The second day I wasn't able to make it for the morning, and …

There is no centralized authentication for mysql. You have to set up your user accounts individually for each of your mysql servers. You can use replication, but that would mean, your master servers must have the same authentication privileges as your slaves have. What about security?

So, here is a little workaround that I did and I can't find the same anywhere.

How does it work?

This is an unofficial and unsupported solution. Let's have a master and one or more slave hosts. On your master, you have to create a database lets say slave_auth. Create the same tables in this database as you have in the 'mysql' database and needed for authentication (more details below), and set up a user who can read/write those tables.

When you are done, create a temporary database on your slaves lets say auth_temp with the exact structure of the tables on your master, but with federated engine connected to your …

This entry is a follow up to TOTD #95 and shows how to use the recent integrations of JSR 299 in GlassFish v3 to convert a JSF managed bean to a JSR 299 bean (aka Web Beans). The TOTD #95 describes a simple Java EE 6 web application that uses Java Server Faces 2.0 components for displaying the results of a database query conducted by EJB 3.1 and JPA 2.0 classes.

The EJB class, which …

This entry is a follow up to TOTD #95 and shows how to use the recent integrations of JSR 299 in GlassFish v3 to convert a JSF managed bean to a JSR 299 bean (aka Web Beans). The TOTD #95 describes a simple Java EE 6 web application that uses Java Server Faces 2.0 components for displaying the results of a database query conducted by EJB 3.1 and JPA 2.0 classes.

The EJB class, which …