I was talking with someone the other day about my Lineo experiences, and it recalled to my mind just how insane the dot-com boom was. Lineo was on a strong path to IPO - we had almost no revenues (a few million dollars), were grossly unprofitable, had no differentiating product (embedded Linux, which customers were happy to buy consulting around, but not pay for the software itself, and wouldn't pay anything for support), and had a massive burn rate.

This was IPO material?

To be fair to us, a large reason that we had the burn rate was because our investment bankers (very respectable, big-name bankers, mind you) told us that we needed a large employee base to justify a high valuation. Think about that for a minute. Not revenues. Not profits. Employees. And so we acquired 6 companies, went from 40 to 440 people virtually overnight, and completed our S-1. …

There was this bug that I wrote about earlier which caused certain Stored Procedures to crash when they were executed more often than once.

I noticed in the bug report and in the change log that this bug will be fixed in MySQL 5.0.23.

I just saw a Microsoft commercial video clip using the slogan

"Better and more simple Visual Basic - goodbye anger, hello fun"

What do they want to tell us? Does that mean, the former version of Visual Studio/Visual Basic caused anger? Do they worsen their old product to make advertising for the new one?

My next thought would be - how will they advertise when the next version comes out? Will they again say, that the now current release causes anger or something similar?

I don't think that's good advertising.

DELIMITER //

CREATE SCHEMA fractal //
USE fractal //

CREATE TABLE disp (
id INT PRIMARY KEY,
content VARCHAR(1000)
) //

CREATE TABLE shade (
id INT PRIMARY KEY,
value INT
) //

INSERT INTO shade (id,value) VALUES (0,ORD(' ')),(1,ORD('.')),(2,ORD(',')),
(3,ORD('-')),(4,ORD('~')),(5,ORD('*')),(6,ORD(':')),(7,ORD(';')),(8,ORD('+')),
(9,ORD('o')),(10,ORD('O')),(11,ORD('&')),(12,ORD('%')),(13,ORD('@')) //

CREATE PROCEDURE mandelbrot (IN x_max INT, IN y_max INT)
BEGIN
DECLARE x INT DEFAULT 0;
DECLARE y INT DEFAULT 0;
DECLARE xf0 FLOAT;
DECLARE yf0 FLOAT;
DECLARE xf1 FLOAT;
DECLARE yf1 FLOAT;
DECLARE tf FLOAT;
DECLARE l INT;
DECLARE l_max INT;
DECLARE buffer VARCHAR(1000);
DECLARE tint INT;
TRUNCATE disp;
SELECT MAX(id) INTO l_max FROM shade LIMIT 1;
WHILE y<y_max DO
SET buffer='';
SET x=0;
WHILE x<x_max DO
SET xf0=x*4.0/x_max-2.0;
SET yf0=y*4.0/y_max-2.0;
SET xf1=xf0;
SET yf1=yf0;
SET l=0;
WHILE l<l_max AND xf1*xf1+yf1*yf1<4.0 DO
  SET tf=xf1*xf1-yf1*yf1+xf0;
  SET …

This document is a user report on the MaxDB Synchronization Manager. The article describes the use of the MaxDB Synchronization Manager during United Drugs Annual Convention from a technical standpoint. It gives an example of the magnitude of possible application of the MaxDB Synchronization Manager. Written for developers, the user report contains warnings on common pitfalls and gives hints how to circumvent the problems.

My friends Theo Schlossnagle, Laura Thomson and Chris Shiflett are each presenting at ApacheCon Europe. They are each excellent presenters with solid content - I have seen Theo present at a previous ApacheCon, caught Laura at several OSCONs and finally saw Shiflett speak at the PHP Quebec conference earlier this year.

The deal is simple - sign up for any of their tutorials before the early bird deadline for the conference closes (on June 6th) and get complementary copies of some of the speaker’s book(s).

The sessions are:

• Advanced Production Troubleshooting …

MySQL does not always make a right decision about indexes usage.
Condsider a simple table:

PLAIN TEXT SQL:

1. CREATE TABLE `t2` (
2. `ID` int(11) DEFAULT NULL,
3. `ID1` int(11) DEFAULT NULL,
4. `SUBNAME` varchar(32) DEFAULT NULL,
5. KEY `ID1` (`ID1`)
6. ) ENGINE=MyISAM DEFAULT CHARSET=latin1

SELECT COUNT(*) FROM t2;
250001 (V1)

SELECT COUNT(*) FROM t2 WHERE ID1=1;
83036 (V2)
(execution time = 110 ms)

That is index selectivity by condition (ID1=1) is V2/V1 = 0.3321 or 33.21%

It is said (e.g. book "SQL Tuning") if selectivity over 20% then a full table scan is preferable than an index access.
As far as I know Oracle alway chooses a full table scan if selectivity over 25%.

…

Finally i was able to do a benchmark of the 3 search engines
- mysql fulltext search
- lucene search engine
- sphinx www.sphinxsearch.com

I came across sphinx while doing a search on full text search engines. It is a very good engine. Few points regarding sphinx
-> Very simple to configure, create index and search
-> Very easy to integrate with php and mysql. APIs for the same are also available. I was able to build index and search using sphinx in a few hours.
-> The index which has been created is a combination of all fields of mysql. There is no distinction between different fields being searched. So you can perform search on an index and not on different fields of the index.
-> Of course since its source code is available, the searching process can be customized according to your needs. Moreover 0.9.6 version …

Paul McCullagh works on a new pluggable transactional Storage Engine for MySQL, called PrimeBase XT. I met him for an interview a few days ago - you can now read it on the MySQL Developer Zone. Enjoy and have a nice weekend!

Let's say that you are building a new application, and you need to test it against a large set of data. You would need either to borrow the data from some known source or to create it yourself.

If you have such collection at your disposal, good for you. But more often than not you need some sort of data that is not ready in your repositories, and then you need to have a quick method to create it.

I will tell you three quick tricks to create large datasets of simple data types, namely numbers, words, and dates.

Le's assume that we need at least one million records. Here's how to go for it.

numbersCreating a large table with just a numeric field is quite simple.

You may be tempted to run a loop in your favorite language, or even in a SQL stored procedure, but this approach would run for quite a long time.
There is a better …