…or I’m doing something stupid, in which case I hope someone would enlighten me.

We grab a number of data from two different MySQL servers, get them back as arrays ($ar1 and $ar2) and then we concatenate the two arrays. $ar1 consists of 30 to 200 elements, sometimes more. $ar2 typically contains 30 elements.

The PHP way of doing this is:

$ar1 = array_merge($ar1, $ar2);

and the home-grown version is

foreach($ar2 as $i) {

 $ar1[] = $i;
}

While I do realize that “the PHP way” involves creating a new copy of $ar1 along the way, my assumption before testing this was that, being an internal function with no further parsing or interpretation to be done, it would be much faster.

Doing some microtime() estimations while keeping $ar2 constant at 30 elements, I found:

• At 1-10 elements in $ar1, array_merge is about 33% faster.
• At 20-40 …

An excellent ending to a great educational day. The party was outstanding. I didn't realize I had so many dance moves left in me. Thanks to the people that showed me some cool dance moves that made me look good.In previous times, people discounted the telephone, automobile and Internet as being toys and play things for people with too much idle time. The same people that laugh at how short

I really enjoyed the Sun Employees Connect event. Sun executives such as Jonathan Schwartz, Martin Mickos, Rich Green, Don Grantham, John Fowler, Karie Willyerd, Hal Stern, Lin Lee shared ideas, perspective and direction for the organization. Sun's innovativeness and strategic directions make it a lot of fun to go to work everyday. I really felt a lot of the same closeness and willingness

I'm travelling to Melbourne in a few weeks, to teach another edition of some Open Query course days. Three days this time:

• Optimisation by Design
• Storage Engine Optimisation
• Replication Workshop

There are still some seats available; you can sign up for individual days, and there's very special pricing available for students! The Melbourne dates are 12-14 May (Monday-Wednesday). I'm doing on-site consulting later in the week.

Interesting Google tech talk: Supporting Scalable Online Statistical Processing.

Goes for an hour and has a slowish start but around the 10 minute mark the beef starts... basically, rather than doing complete aggregates, he uses statistical sampling to provide a reasonable estimate (unbiased guess) of the result.

This makes sense, statistically!
It might be possible to transplant his system into a MySQL storage engine, but it would need to be able to do in-engine joins, something that MySQL doesn't yet support.

(Thanks Ian for the link)

Maybe this was the 0th week!

Yep, I started working on Summer of Code project little by little,
one day after another.

On Monday, I got really excited when I realized that that e-mail from
Google entitled “Congratulations” was addressed to me, not to the
student list… indeed, I noticed that more than a hour after I first
read it (I was really heedless in doing that, don’t you think?). The
Web app did not show the accepted proposal yet, so I went to sleep but
was not able to stop thinking (at least for some time :-).

On Tuesday I woke up with the news I’ll work on the implementation of
a new storage engine for the MySQL DBMS: pretty exciting wakening! To
tell the truth, I was a little worried, because this was absolutely
not the simplest project I could have been chosen to …

A well thought backup saved my skin last Saturday.
It's a simple setup: many copies. Using MySQL replication, the master is for writes.
Four slaves for reads. One slave for backups only (*). In a different server room. In a different building. (**)
The backup slave has a  cron job, which stops the slave, makes a dump, removes the oldest one, and resumes replication.
The same job works hourly (keeps 30 dumps), daily (keeps 7 dumps), and weekly (keeps 8 dumps).
The disaster occurred yesterday. A colleague who was working too much (***) made a destructive query on the wrong server. He thought he was using the development server, but it turned out to be the master. Fortunately, nobody else was working on a Saturday, so there weren't any changes, besides his. I zeroed the database on the master and reloaded the latest hourly dump. No suffering. No bad …

Sarah already wrote something about the PHP Unconference, but Mayflower sent a bigger team, so here are some more impressions.

The unconference had a fair share of the "ever-present" people in PHP development and the corresponding open-source community and also people interested in recent features and willing to learn although they came from different backgrounds. This avoided most of the low-level noise and kept the weekend on a very high level.

Both days there were 4 session tracks with 4 talks each for an admirably rich choice of 32 possible sessions, which made it very hard to get hold of everything you're interested in, but this was deliberately planned and I didn't attend a single talk I didn't like. The long coffee-breaks had a very intense tendency to keep the people busy discussing technical questions or just general chatter with old acquaintances that the orga team was busy driving the people to the talks …

Last weekend the PHP Unconference took place in Hamburg. With about 120 participants it took awhile to vote for the offered talks but at the end more than 30 sessions appeared on the agenda for two days and that promised to be an exciting weekend. You'll find all topics and summaries on PHP Unconference Wiki. There were many interesting sessions for choice, for example 'MySQL Performance Tuning' by Kris Köhntopp, with which started the first day. 45 minutes, as it turned out, were not long enough for this talk and I would have liked to hear more about it. During the talk 'Ask the core developer' by Johannes Schlüter the current moods and the future of PHP and the community were discussed, yet not all of the attendees had the same opinion about that. Security, too, was a topic of the unconference and Johann-Peter Hartmann had …

How do you configure python for use with mysql? You require the MySQLdb module for connecting to mysql server using the python code. This module is used for firing queries to the database server and handling of result sets from python code.

First of all, check if the module is available or not :

jayant@jayantbox:~$ python Python 2.5.2 (r252:60911, Apr 21 2008, 11:17:30) [GCC 4.2.3 (Ubuntu 4.2.3