Sun Microsystems - Australia - APAC Extended Horizons Summit 2008

I’m giving a Cluster session tomorrow (Sunday) and talking about Scaling MySQL on Monday. Hope to see you there!

I'm not big fan on flow control functions like IF or CASE used in MySQL Queries as they are often abused used to create queries which are poorly readable as well as can hardly be optimized well by MySQL Optimizer.

One way I find IF statement very useful is computing multiple aggregates over different set of rows in the single query sweep.

Here is how I like to use it for web site performance analyzes. As you can see in this table we have recorded "wtime" which is wallclock time it took to generate the page. We also track types of pages because they often have different performance profile.

PLAIN TEXT SQL:

1. mysql> SELECT count(*) cnt, avg(wtime) avw, sum(IF(wtime>0.3,1,0))/count(*) soso, sum(IF(wtime>1,1,0))/count(*) poor, sum(IF(wtime>5,1,0))/count(*) fatal FROM performance_log_080523;
2. +---------+------------------+--------+--------+--------+
3. | cnt  …

Marten Mickos sara' presente a un evento presso l'Universita' La Sapienza di Roma, Venerdi 30 Maggio.
Marten parlera' della sostenibilita' del modello Open Source, del presente e del futuro di MySQL.L'agenda e il modulo di iscrizione, per chi fosse interessato, e' disponibile qui.
In coda all'intervento di Marten, parleremo di scalabilita' e compareremo l'approccio alle architetture basate su MySQL rispetto a quelle utilizzate con altri database relazionali.
Giuseppe Maxia illustrera' il ruolo della Community nell'eco-sistema di MySQL e spieghera' come e' possibile contribuire al miglioramento dei prodotti e delle soluzioni. 
Ci sara' anche spazio per un'ampia sezione di domande e risposte... meglio approfittarne!
Spero di vedervi numerosi a Roma!
-ivan

Are you ready for the next webinar? This time we will talk about the use of MySQL with memcached. Most of you may already know memcached and how to use it in a typical web environment with high traffic and requirements for high scalability.

During the webinar we will cover different scenarios and best practices regarding the use of MySQL and memcached together.

The webinar will be live next week, Wednesday 28th of May @ 9am GMTD (London, Dublin, Lisbon) / 10am CETD (Paris, Madrid, Munich, Rome etc.)

The registration is available here.
I hope to see you all online next week!
-ivan

Le slide e la registrazione del webinar che si e' tenuto il 7 Maggio scorso, sono disponibili qui.
Di seguito ho preparato la sessione di domande e risposte.

Q from Andrea: E' possibile creare un sistema multi-master tramite l'assegnazione di impostazioni auto_increment_offset  diversi?
A: Si, questo e' il meccanismo piu' tipico. Ogni server master utilizza un diverso offset per creare una PK e quindi inserire nuove righe nella stessa tabella, quindi

Q from Massimo: Cosa succede se viene effettuata una lettura su uno slave di alcuni records modificati nel master e non ancora replicati? si puo prevenire questa situazione?
A: La situazione si puo' prevenire, ma la logica da applicare e' abbastanza complessa. Detto questo, se le specifiche richiedono questo tipo di lettura aggiornata in real …

For those that have my existing blog bookmarked, or use any RSS/Atom feeds please update your information now.

My new blog can be found at http://ronaldbradford.com/blog/

RSS 2 is http://ronaldbradford.com/blog/feed/rss2, Atom is http://ronaldbradford.com/blog/feed/atom

Ok, so before you read on please change now. While all old links will redirect I encourage you to take a few moments in your browser and RSS reader.

So what’s new. Well as Baron stated in I moved this blog to pairLite with zero downtime, and it was easy I moved my old blog site blog.arabx.com.au and my …

Kaj just announced that as of 5.1.25, MySQL Cluster will no longer be included in the normal MySQL packages. Instead, a new branch is being created for MySQL Cluster releases, where the first release is informally called “6.2.15″ but the releases are really named “mysql-5.1.23-ndb-6.2.15″. This new branch is based on the MySQL Cluster Carrier Grade Edition of MySQL.

Overall, this seems like a good idea — the needs for releases, schedules, pressures, etc., are at odds between MySQL Cluster and MySQL’s core. I am, however, baffled by the decision of how to release the new product: coupled with MySQL as a single monolithic package with compiled-in storage engine. After all, 5.1 has long been touted to have this amazing new …

MySQL’s version numbering is getting harder and harder to understand. In fact, it’s getting surreal.

Let me state up front that there’s probably a lot I don’t know here. But if I don’t know, how on earth can the general public figure it out?

Before we begin, let’s define terms: GA is completely done, ready for use. RC is a release candidate: don’t change anything, just fix bugs because we’re charging towards a release here. Beta is possibly unsafe code, use at your own risk. Alpha is known to have significant bugs, but if you’re curious please play with it.

Now for the releases/versions game. Let’s recap:

• 5.0 has version numbers that leapfrog each other in features and functionality. SHOW PROFILES — now you see it, now you don’t.
• 5.1 has been “… released to general …

On Monday this week I attended the first day of the Ubuntu Developer Summit in Prague.  The summit which just ended today, was intended to drive plans and decisions for the next Ubuntu release "Intrepid Ibex" which is due out on October 30th.  (Check out the reports from the summit here.)

Mark welcomes the masses while Jono scans the crowd for hecklers.

Sun had about 12 folks there representing GlassFish, Open JDK, NetBeans, Hudson, …

I've run some data load tests with various databases using DBMonster, so connecting to databases through JDBC on a WindowsXP personal computer.Here are the results, in both cases I loaded 100 rows in the parent table and 1000 in the child table, with foreign keys enabled.Firebird 2.1 with Jaybird 2.1.3 and DBMonster 1.0.3 (And Java .6)Table structure is:CREATE TABLE GUYS(GUY_ID Integer NOT NULL,