MySQL, MSSQL and Oracle SQL Injection Compilation

This Knowledge Base was put together and is maintained by Roberto Salgado, Co-Founder of Websec. It is a compilation of books, papers, cheatsheets and testing done by Roberto over the years. » Roberto Salgado | websec.ca

July 15, 2012 · 1 min · 36 palabras · Nacho Cano

A Visual Git Reference

This page gives brief, visual reference for the most common commands in git. Once you know a bit about how git works, this site may solidify your understanding. » Mark Lodato | marklodato.github.com

July 15, 2012 · 1 min · 33 palabras · Nacho Cano

Levels of aspiration

Debates over technology, technique, and process often go nowhere because the participants are arguing from different levels of aspiration. You’re unlikely to convince someone they should switch to programming Ruby for its beauty, if they’re merely looking to make a living as a single consultant serving local businesses in Schaumburg, Illinois. Questions such as ”does this run on my existing web host?” or ”will my clients want something their nephew web designer hasn’t even heard of?” matter far more. Their aspirations are local, finding something that (sorta) works, and getting paid. ...

July 15, 2012 · 1 min · 95 palabras · Nacho Cano

¿Existen los colores en la naturaleza?

Aparentemente esta pregunta parece absurda, ¿Como no van a existir los bellos colores de los paisajes que podemos observar a diario? El azul del cielo, el verde de las hojas de los árboles… parece evidente que los colores existen y son uno de los atributos más fundamentales de todos los objetos que observamos. Sin embargo, como veremos a continuación la respuesta a esta pregunta es asombrosa e inesperada. Lo primero que tenemos que hacer para tratar de responderla es analizar brevemente como y por que vemos los objetos que nos rodean. ...

July 15, 2012 · 1 min · 93 palabras · Nacho Cano

Statistical functions in MySQL

Even in times of a growing market of specialized NoSQL databases, the relevance of traditional RDBMS doesn’t decline. Especially when it comes to the calculation of aggregates based on complex data sets that can not be processed as a batch like Map&Reduce. MySQL is already bringing in a handful of aggregate functions that can be useful for a statistical analysis. The best known of this type are certainly: COUNT(x), SUM(x), AVG(x), MIN(x), MAX(x), STD(x) In addition, there are a number of statistical evaluations which are also worthwhile - if not even more interesting and meaningful, but with MySQL only producible with greater efforts. What about the different averages? The harmonic average, a weighted average or the geomean? What is in the course of this with the aggregate product? How do we determine the mode, the median? The covariance? ...

July 14, 2012 · 1 min · 206 palabras · Nacho Cano

Ready-to-use virtual machines sporting open-source operating systems

We provide pre-built images for several open-source operating systems. Please note that: Every image contains the latest software as of the day the image was built. Performing updates is on your own, and may require looking for documentation to read using your favourite search engine. Default usernames and passwords, where required, can be found next to the download link of each image. You are warmly invited to create your own user, or at least to change passwords, if you intend to use the images in a public environment. ...

July 14, 2012 · 1 min · 90 palabras · Nacho Cano

Cómo medir la eficiencia energética de tu propio coche

Pere Roura (Universitat de Girona) y Daniel Oliu nos cuentan en ”How energy efficient is your car?,” AJP 80: 588-593, July 2012, cómo medir de forma práctica la eficiencia energética de tu propio coche. Como ejemplo utilizan su Volkswagen Lupo 3L, un coche diseñado para ser muy eficiente con un motor diésel de tres cilindros, un peso de 830 kg y un consumo récord de solo 3 litros a los 100 km. Según su estudio solo el 28% de la energía del combustible se transfiere a las ruedas, lo que sin lugar a dudas es todo un récord en eficiencia para un vehículo comercial. Sin embargo, también nos recuerda que el 72% de la energía del combustible se pierde por aerodinámica, fricción, pérdidas mecánicas y térmicas. En los vehículos de gasolina, la eficiencia suele ser mucho menor. Para un vehículo típico se estima que solo el 12-13% de la energía del combustible se transmite a las ruedas, según el estudio de Joseph A. Carpenter, Jr. (Department of Energy, USA) et al., ”Road Transportation Vehicles,” MRS Bull. 33: 439–444, 2008 [copia gratis], del que he extraído la figura de abajo. ...

July 14, 2012 · 2 min · 303 palabras · Nacho Cano

Preliminary discussion of the logical design of an electronic computing instrument

Arthur W. Burks / Herman H. Goldstine / John von Neumann PART I ​1. Principal components of the machine 1.1. Inasmuch as the completed device will be a general-purpose computing machine it should contain certain main organs relating to arithmetic, memory-storage, control and connection with the human operator. It is intended that the machine be fully automatic in character, i.e. independent of the human operator after the computation starts. A fuller discussion of the implications of this remark will be given in Sec. 3 below. ...

July 13, 2012 · 2 min · 233 palabras · Nacho Cano

Scaling lessons learned at Dropbox

I was in charge of scaling Dropbox for a while, from roughly 4,000 to 40,000,000 users. For most of that time we had one to three people working on the backend. Here are some suggestions on scaling, particularly in a resource-constrained, fast-growing environment that can’t always afford to do things ”the right way” (i.e., any real-world engineering project ;-). If people find this useful, I’ll try to come up with more tips and write a part 2. ...

July 13, 2012 · 1 min · 82 palabras · Nacho Cano

The Complete Wildfire Index (Root/S-OFF Guides/ROMs/Kernels/Radios/RUU/Recoveries/Themes)

This thread has 2 Posts, and is categorized as following. You can scroll down to the Point you are looking for. Post 1: Getting Root / S-OFF to your Wildfire. A Short overview and Guide Custom ROM List Post 2: Custom Kernels List Radio (Baseband) List RUU List (ROM Update Utility - Getting back to stock) Custom Recoveries (ClockWorkMod) Themes List Misc tweaks / hacks » 3xeno | xda-developers.com

July 13, 2012 · 1 min · 69 palabras · Nacho Cano