Tags: [ cybos ] [ operatingsystem ] [ tutorial ]
Somewhere in 1998 or even earlier, I started my own little project in creating a - functional - Operating System from scratch. Not a linux clone and not a MS-DOS wannabe. Just a simple OS that is functional in such that some tools, games etc could actually work, not caring about Posix compliance, fancy graphics or all hardware support you can think of..
So, today, 12 years later, where are we?
Tags: [ MySQL ]
Cardinality and selectivity are two keywords that are very important when dealing with optimization in MySQL queries and indexes. This article will go a bit in depth on both terms and tries to let you understand their usefulness…
Tags: [ PHP ] [ pack ] [ unpack ]
Nowadays most lowlevel functionality like reading or writing graphics are taken care of 3rd party libraries
and that’s ok. It’s way to complicated to do things right and you probably want to focus on outputting or
sending a PNG instead of construction one from scratch. While reading and writing these kind of binary data
was normally done in languages like C or even assembler, most higher level languages still have these
capabilities and yes, even PHP… Meet
Tags: [ email ] [ validation ]
Error: Your email address is invalid.
Every time I see those or similar words when I fill out a registration form I start to cry a little. It’s not my email address that is invalid, it’s the websites email validation functionality and it’s a great and effective way to loose visitors and/or customers quickly.
Tags: [ keyword ] [ opensource ] [ plugin ] [ TinyMCE ]
Tags: [ covering ] [ index ] [ MySQL ]
It’s almost to easy to use a
SELECT * FROM query in your code. First of all, you instantly get all the
fields from your database so you don’t have to worry about changing your queries when you decide to use other
fields (in case you don’t use a DAL). However, there are some drawbacks on a
SELECT * method,.. the most
famous one: it takes more time to retrieve all fields instead of the fields you actually use.. but that’s NOT
the most important reason why you should not
SELECT * FROM queries..
The main reason? Covering indices…
A lot of people are telling me to write some posts because I apparently have interesting stuff to say once in a while. This is the place I have picked out to do so. Since I don’t have a single area of expertise (or one could say, I’m an expert in ALL area’s :)), this will probably be a place of a lot of stuff you will find interesting, and a lot of things you don’t. Don’t worry, you are not alone :)
Tags: [ Big-O ] [ PHP ]
Normally you would develop against a test-database. It probably contains about 10 people so you can do your programming and testing.. Once it’s done and QA’d, it will go live and people start to visit the site. After a year or so,.. the site is too slow. Adding more db servers is of no use, your system administrator is spending his holiday inside the my.cnf’s and after dumping a gazzilion GB’s of extra memory to the systems doesn’t help at all… Sounds like it’s the code that’s falling behind.. it cannot cope sorting or handling user lists of 40.000 people, or arrays with more than a million items and even simple validation functions are way to slow.. why? what just happened?