Performance-wise, the idea of Prepared Statements is that the server does certain pre-processing on PREPARE command, and then those steps are omitted when the statement is executed. If the statement is executed several times, we get an economy of

cost_of_prepare_preprocessing * (#statement_executions - 1)

This makes one want to move the CPU and IO-intensive query optimization into the PREPARE phase. Unfortunately, this will make the optimizer work much worse - optimizer's decisions are based on the external information, and there is much less available information at PREPARE phase. The most crucial differences are that

• The values of the '?' parameter markers are not yet known
• The results of probes done in the the queried tables cannot be relied on because the table data may change before the EXECUTE
• [less important] Table and index statistics may change before the EXECUTE

…

Jonathon Coombes recently blogged in MySQL Cluster Certified that he passed the MySQL Cluster DBA Certification as was the first Australian. Lucky for him I passed the exam after my presentation on the second day of the conference. I guess us Australian’s are leading the world!

As Jonathon said it was rather hard, certainly more difficult then the other DBA exams but nothing for an experienced Cluster DBA.

Today someone sent me an exploit for the Windows version of XAMPP: Using our xampp/adodb.php and a buffer overflow vulnerability in mssql_connect() the exploit is able to call arbitrary(!) commands on the targeted system.

If you secured your system as described in our manual, you're a lucky guy and your system is not affected by this vulnerability.
If you haven't secured your system, please do it right now!!!

YOU SHOULD USE NDB/BINDINGS WHICH YOU CAN FIND HERE! NDB/BINDINGS IS THE OFFICIAL VERSION BEING MAINTAINED AND INCLUDES NDB/J.

IGNORE EVERYTHING BELOW THIS POINT (except the first couple of sentences):

NDB/J is a type II Java connector that makes it possible for a Java application to connect directly to the NDBCluster storage engine, thus by-passing the MySQL Server.
Initial benchmarks we have conducted shows that NDB/J is in parity with the C++ NDBAPI when it comes to performance. Moreover, NDB/J is a wrapper of the C++ NDBAPI, but offers Java-like abstractions such as Exceptions and ResultSets.

If you are interested in evaluating NDB/J and trying it out, you can download it here.
The following versions of MySQL Cluster should work:

• MySQL …

In my fourth day at the MySQL Conference and Expo 2007, I attended several great sessions, starting with my own.

Pasha Sadri from Yahoo gave the final keynote presentation at the mySQL conference on his work with Yahoo Pipes. He began his presentation talking about problems he was having grinding through craigslist and other RSS feeds to extract useful information. He thought about how he could build something that solved similar problems for others trying to do the same kinds of things.

Pipes is a RSS mashup tool that allow you to combine RSS feed and apply transformations on the data and create a new feed. If you haven’t seen it, you ought to check it out. Several good technical reviews here, here and …

I recorded many of the sessions I attended at the conference. You can download the audio files in Ogg Vorbis format here. These files will not stay up forever – I will probably remove them after a few weeks. My recorder only records in mp3 format, so I was forced to crank the bitrate down pretty far to avoid ending up with gigabytes of data. Too bad it doesn’t record directly to Ogg Vorbis format; if it did, I could get natural-sounding voice-quality at something like 8 kB/sec.

On advice of the MySQL She-BA, I wanted to see what performance I could get with MERGE tables. In my particular application I'm going to need the RI I get with InnoDB, so it's not a solution, but as long as I am investigating anyway...

Seems simple enough, let me the MERGE table over my existing tables:

mysql> create table xyz_mt (
    -> `id` bigint(10) NOT NULL default '0',
    -> `report_dt` date default NULL,
    -> `acct_id` varchar(8) default NULL,
    -> `some_text` varchar(222) default NULL,
    -> PRIMARY KEY (`id`)
    -> ) ENGINE=MERGE UNION=(xyz_2007_01,xyz_2007_02,xyz_2007_03) ;
Query OK, 0 rows affected (0.08 sec)

mysql> select id, report_dt, acct_id 
    -> from xyz_mt 
    -> where report_dt ='2007-02-17' 
    -> and acct_id = 'X0000741';
ERROR 1168 (HY000): Unable to …

Its a rare day where I can get HP, IBM, Oracle, Solid, and Google in a room to talk about our storage engine API. Especially when it is several VP's, Directors, and Senior Engineers.

Today is the day :)

We are spending a day at Google, thanks to Chris Dibona, going over the API. It was a great time to get everyone together since thanks to the User's Conference everyone was in town.

No NDA's, just engineers talking about code!

While I'm being insane...

CREATE TABLE housing ...
 ENGINE=FEED
 CONNECTION="http://seattle.craigslist.org/hhh/index.rss";

SELECT title FROM housing WHERE ...;


I think I can get it working with a week or less work.

I thought of doing this at the Yahoo Pipes talk at the Vancouver PHP conference a few months ago, but dimissed it as a joke. I thought of it again at Pasha Sadri of Yahoo's final keynote yesterday. This time, I know that I can do it, but I don't know if I can dismiss it as a joke.

Is this a great idea, or a sick one?