RAW Things

30 Nov · Robert Eisele

Setting Up a Secure Email Server with Postfix, Dovecot, and MySQL on Debian/Ubuntu

Configure Postfix, Dovecot, and MySQL with DKIM, SPF, and SpamAssassin for a secure, efficient, and spam-resistant email server.

26 Aug · Robert Eisele

High-Power Devices with Arduino and TIP120 Transistor

04 Aug · Robert Eisele

How to use the MCP4251 Digital Potentiometer with Arduino

04 Aug · Robert Eisele

Programming the ATtiny85 Using Arduino

06 Jul ·

OpenSCAD Polygons with Rounded Corners

01 Apr · Robert Eisele

jQuery color plugin xcolor

17 Aug · Robert Eisele

Catch It! HTML5 Game

10 Jul · Robert Eisele

lighttpd mod_mysql_accesslog

08 Jun · Robert Eisele

How to use a Nokia 5110 Graphical Display with Arduino

How to use a Nokia 5110 or Nokia 3310 Graphical Display using the Philips PCD8544 Controller with Arduino

13 Mar · Robert Eisele

DIY Ohmmeter to Measure Resistor values with Arduino

How to build an ohmmeter cheap and quickly with an Arduino using a voltage divider

15 Mar · Robert Eisele

Set Excel columnWidth Property in Points with VBA

How to set the Excel columnWidth property with VBA in points (centimeter and millimeter)

14 Jul · Robert Eisele

Operate a Syma S107G Remote Control Helicopter with an Arduino

A deep dive into the remote control toy helicopter Syma S107G to get controlled with an Arduino board

11 Jul · Robert Eisele

Using Gamepads in JavaScript via node.js

A node.js library to work with Sony PlayStation controllers, Microsoft XBOX controllers SNES or a bunch of other controllers

03 Jul · Robert Eisele

Set up Internet Sharing on Mac OSX using Command Line Tools

A working solution to set up internet sharing without the system preferences but command line tools

27 Jun · Robert Eisele

A pure JavaScript DHCP implementation

How to implement a DHCP server and a DHCP client in JavaScript to get access to raw packages

20 Jul · Robert Eisele

Enable Key Repeat in Mac OS-X and disable Character accent Menu

If you want to change the new behavior of showing an accent-menu instead of repeating keys in OS X, this trick may help you.

19 Dec · Robert Eisele

Using a Wii Nunchuk with Arduino

How to hack a Wii Nunchuk to make it work with Arduino

30 Nov · Robert Eisele

Creating an Advent Calendar with HTML5 and CSS3

How to create an Advent Calendar with HTML5 and CSS3 with a nice 3D effect

29 Jul · Robert Eisele

How to write a PHP Daemon

A full course into how to write a unix style daemon in PHP

08 Jul · Robert Eisele

Store a tag-cloud in MySQL

A simple approach to guide you throw the steps needed for a tag-cloud stored in a MySQL database

08 Jul · Robert Eisele

Simultaneously set and delete bit flags in a database

A proof to get to a simple expression for bit flag deletion and setting

06 Jul · Robert Eisele

Using GPS with node.js and JavaScript

An introduction to the GPS.js library

02 Jul · Robert Eisele

Complex Numbers in JavaScript

A well optimized complex numbers library in JavaScript

20 Jun · Robert Eisele

Importing entire Wikipedia into MySQL

How to import the entire Wikipedia corpus into MySQL with database installation, creation and actual import

13 Jun · Robert Eisele

Forcing Garbage Collection in node.js and JavaScript

How to force the garbage collector in node.js and V8

10 Jun · Robert Eisele

NEO6MV2 GPS Module with Raspberry PI

10 Jun · Robert Eisele

NEO6MV2 GPS Module with Arduino

Set up a serial GPS module with Arduino

12 Mar · Robert Eisele

Rational numbers in JavaScript

A rational numbers library in JavaScript for more precise calculations

05 Mar · Robert Eisele

JavaScript Bit Array

An optimized JavaScript Bit Vector Implementation

19 Aug · Robert Eisele

Running Standard Deviation in MySQL

Calculating the standard deviation without using MySQL's aggragate function STD, but by implementing it by yourself.

16 Jul · Robert Eisele

Optimal index size for variable text in MySQL

Release of a small database auxiliary query to choose the correct index size of a column.

14 Jul · Robert Eisele

Statistical functions in MySQL

A list of standard formulas for a statistical analysis with MySQL. Additionally some new functions are introduced via the infusion UDF

12 Jul · Robert Eisele

MySQL Infusion UDF for statistical analysis

An update of the MySQL infusion UDF in order to add new statistical functions to the MySQL core.

27 Oct · Robert Eisele

Flag based COUNT using MySQL

Counting flags in an optimized manner. Normally, the cardinality of flags in databases is very poor so that a different approach must be used.

24 Oct · Robert Eisele

Optimized Pagination using MySQL

How to implement an optimized pagination with MySQL?

04 Sep · Robert Eisele

jQuery Pagination revised

The best pagination plugin on the market. It combines the features of all available plugins through a distinct and easy callback interface.

10 Jun · Robert Eisele

Faster PHP behind FastCGI

A simple approach improving the performance in real world environments by reducing the number of copies of the entire DOM.

08 Jun · Robert Eisele

PHP Hacking

An extensive PHP fork with changes to the core in order to improve performance, usability and flexibility.

20 Jan · Robert Eisele

Find friends of friends using MySQL

A list of MySQL views to get the friends of friends (FOF) from a certain user of a social network.

14 Aug · Robert Eisele

Tag Cloud plugin for Smarty

An extensive Smarty plugin to create tag clouds based on some simple metrics.

12 Jan · Robert Eisele

Create a simple and small GIF with PHP

A small PHP function to create the smallest GIF possible by the standard in any color you'd like.

10 Jan · Robert Eisele

Is it possible to avoid query parsing inside of MySQL?

A question to the MySQL community...

17 Nov · Robert Eisele

MySQL - My new playground

A MySQL UDF to simplify some queries handling with binary, string and group data in a special way.

08 Nov · Robert Eisele

Transparent query layer for MySQL

A query abstraction layer which uses a prepared statement similar approach to inject cluster management transparently.

17 Sep · Robert Eisele

Camara support in HTML5 and JavaScript

Native webcam support for HTML5 by using a bridge to Flash in order to solve the technological gap

02 Sep · Robert Eisele

Resolve many-to-many relations a bit different with MySQL

An attempt to store a CSV list of ID's instead of a fully normalized table design to improve index size and to save grouping.

21 Jul · Robert Eisele

SQL-modes right to exist

An analysis of whether MySQL's SQL mode has still a right to exist. Result: It depends!

19 Jul · Robert Eisele

Use MySQL binlog to collect accesslogs

A lighttpd plugin to use MySQL's replication mechanism to collect accesslogs from several webservers.

07 Jul · Robert Eisele

My jQuery Playground

Two new jQuery plugins just arrived. A color calculation plugin and a plugin to manage your border radius

29 Jun · Robert Eisele

Combine CSS and JavaScript with lighttpd

An approach of combining static data on the fly using lighttpd's mod_magnet to reduce the number of requests.

28 Jun · Robert Eisele

Optimized way of getting subqueries at once using JSON

Retrieving nested data with a single query using JSON as the transport layer.

07 Jun · Robert Eisele

Disable ON UPDATE CURRENT_TIMESTAMP in MySQL

How to avoid triggering ON UPDATE CURRENT_TIMESTAMP in MySQL?

04 Jun · Robert Eisele

Analyze online behavior with MySQL and PHP

An algorithm to determine when users of a website or a community are mostly online in average.

29 Apr · Robert Eisele

Optimizing integer multiplication

A mathematical approach of optimizing integer multiplications for slow MUL instructions and known constants.

28 Apr · Robert Eisele

Dynamic thumbnail generation on the static server

Images are needed in several sizes on a website. Generating every file consumes a lot of disk space. Caching only the sizes they are really requested...

08 Apr · Robert Eisele

Write data asynchronously to MySQL

What is the most effective way of writing data asynchronous to the database? APC queue, file based queue, Gearman, zeromq, all of them have it's right to exist.

24 Mar · Robert Eisele

Generate client-side PNG files using JavaScript

A pure JavaScript implementation of PNG to draw images directly in the browser without a canvas.

17 Feb · Robert Eisele

My very first Chrome experiment

A little HTML5 game which shows the capabilities of the new HTML5 canvas object.

27 Dec · Robert Eisele

MySQL Wishlist

My open feature request to the MySQL database server.

27 Dec · Robert Eisele

Sorted Array to MySQL

Retrieving a sorted list from a database is easy. But how do you store a list of numbers in the same order like in an array to MySQL?

27 Dec · Robert Eisele

Fulltext GEO Search with MySQL

Fulltext GEO search with MySQL. Additionaly, the population improves the weight for a fair ranking.

27 Dec · Robert Eisele

Debian lighttpd startup script

A small Debian bash script to startup lighttpd webserver. There is also an official one but when compiling the package for yourself you have to use your own.

27 Dec · Robert Eisele

Field size as power of two

Is there a difference in using powers of two as field size in MySQL or is this just a nerdy habit?

27 Dec · Robert Eisele

Age calculation with MySQL

How to calculate a human age based on two date values using MySQL? Here is a simple function which does this for you.

27 Dec · Robert Eisele

People near you with MySQL

Find locations around location with an optimized R-Tree index using MySQL MyISAM.

27 Dec · Robert Eisele

PHP Enhancement

A PHP library which adds a bunch of new functions to the core, which could be found in the one or the other project as global addition.

27 Dec · Robert Eisele

Store small numbers in big numbers

A small mathematical digression about storing small numbers in a larger bit range to save memory, disk space and index sizes.

25 Oct · Robert Eisele

How I've got no new .de domain

My fabulous attempt of getting no new 2-3 digit .de Domain. But I ended up with a nice research on weighting good names.

23 Oct · Robert Eisele

Write a PID file in bash

How to write a PID file and spawning a daemon in one single command?

30 Sep · Robert Eisele

Fast circular buffer in MySQL

A simple ring buffer implementation in MySQL with an optimization attempt to max out the performance of the fix sized buffer.

26 Sep · Robert Eisele

Global Constants with PHP

A flexible constant management library for PHP which helps to implement a centralized and easy configuration of your application servers.

25 Jul · Robert Eisele

Simple System monitoring with PHP

A simple PHP extension to tell reverse proxys and loadbalancers that the backend is overloaded. The extension sits between the PHP core and the script.

24 Jul · Robert Eisele

Add HTTP Response Headers in lighttpd

A simple FastCGI programm to add response headers to lighttpd when PHP and LUA isn't an option.

22 Jul · Robert Eisele

Face detection with PHP

PHP Facedetect Extension. The OpenCV wrapper for PHP allows you to detect faces on images and to retrieve their X/Y coordinates.

21 Jul · Robert Eisele

Get the last percents out of lighttpd

A simple lighttpd path which improves the internal constant string handling. The patch is already implemented in the stable release.

21 Jul · Robert Eisele

Logical operations with NULL

NULL values have different meanings in PHP and MySQL. Here's a little explanation after a short analysis.

20 Jul · Robert Eisele

Punycode with PHP

A libidn wrapper for PHP which allows you to generate Punycode from Unicode through a simple API.

14 Mar · Robert Eisele

HTML Particleline

14 Mar · Robert Eisele

HTML5 Boomshine

14 Mar · Robert Eisele

Play classic Snake Game Online

14 Mar · Robert Eisele

Follow the Swarm

14 Mar · Robert Eisele

3D Wire Creator

14 Mar · Robert Eisele

Starship Shooter

14 Mar · Robert Eisele

Winamp Equalizer

14 Mar · Robert Eisele

Bubble Drag

14 Mar · Robert Eisele

Bubble Evolution

14 Mar · Robert Eisele

PHP Infusion Extension

14 Mar · Robert Eisele

PHP Defcon Extension

14 Mar · Robert Eisele

PHP Sysload Extension

14 Mar · Robert Eisele

PHP Facedetect Extension

14 Mar · Robert Eisele

PHP IDNA Extension

09 Mar · Robert Eisele

Precise 220V AC Frequency Measurement with Arduino

16 Dec · Robert Eisele

Play HTML5 Tetris with AI

HTML5 Tetris is a fully customizable Tetris game with optional AI feature.

16 Dec · Robert Eisele

HTML5 Kinematic Clock

14 Jul · Robert Eisele

Trackball Rotation using Quaternions

The Arcball or Trackball is an elegant and intuitive input method to rotate and manipulate a three-dimensional scene with the mouse. With Trackball.js...