beer planet

The Problem

I've had MySQL on my Windows 7 laptop for a bit (as part of wampserver), mostly for local offline Wordpress development.

However, even though MySQL is relatively stable, I've been observing a vast quantity of intermittent MySQL errors, as reported by Wordpress in the PHP error log (C:\wamp\logs\php_error.log). Here are some examples:

[05-Jan-2010 09:47:51] WordPress database error Error on delete of

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Updated: September 28th, 2009

In the past few weeks I've been implementing advanced search at Plaxo, working quite closely with Solr enterprise search server. Today, I saw this relatively detailed comparison between Solr and its main competitor Sphinx (full credit goes to StackOverflow user mausch who had been using Solr for the past 2 years). For those still…

Updated: January 18th, 2010

Introduction

StackOverflow is an amazing site for coding questions. It was created by Joel Spolsky of joelonsoftware.com, Jeff Atwood of codinghorror.com, and some other incredibly smart guys who truly care about user experience. I have been a total fan of SO since it went mainstream and it's now a borderline addiction (you can…

Introduction

A question I recently saw on Stack Overflow titled Faster way to delete matching [database] rows? prompted me to organize my thoughts and observations on the subject and quickly jot them down here.

Here is the brief description of the task: say, you have 2 MySQL tables a and b. The tables contain the same type of data, for example log entries. Now you want…

Updated: June 9th, 2009

Introduction

If you, like me, are building or thinking of implementing a MySQL-powered application that has any need for prioritizing selecting certain data over other data, this article is for you.

Example

As a real world example, consider a queue-like video processing system. Your application receives new videos and processes them. The volume of incoming videos can at times be higher than the processing rate because the process is CPU…

Updated: June 9th, 2009

Today I had to swap 2 columns in one of my MySQL tables. The task, which seems easily accomplishable by a temp variable, proved to be a bit harder to complete. But only just a bit.

Here are my findings:

1. The

   UPDATE swap_test SET x=y, y=x;

   approach doesn't work, as it'll just set both values to y.

   PostgreSQL seems to handle this query differently, as it apparently

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Updated: June 9th, 2009

Introduction

Clickjacking is a malicious technique of tricking web users into revealing confidential information or taking control of their computer while clicking on seemingly innocuous web pages. A vulnerability across a variety of browsers and platforms, a clickjacking takes the form of embedded code or script that can execute without the user's knowledge, such as clicking on a button that appears to perform another function (credit: Wikipedia).

Clickjacking is…

Everyone and their mother are throwing out their predictions for 2009 nowadays, it’s a new fad. It’s like you’re not cool anymore if you don’t have twitter, a Mac, and a set of random predictions for the next 12 joyous months.

So I decided to throw in a few ideas of my own to be part of the cool crowd again (how much cooler can I be already, you…

Updated: June 9th, 2009

During my day-to-day activities, I use the Bash shell a lot. My #1 policy is to optimize the most frequently used activities as much as possible, so I’ve compiled these handy bash shortcuts and hints (tested in SecureCRT on Windows and Konsole on Linux). The article only touches on the default bash mode – emacs, not vi. If you haven’t specifically assigned your shell mode to vi (set –o vi),…

I just came upon a pretty good Hadoop introduction paper posted on Sun’s wiki. Apache Hadoop is a free Java software framework that supports data intensive distributed applications. It enables applications to work with thousands of nodes and petabytes of data. Hadoop was inspired by Google's MapReduce and Google File System (GFS) (wikipedia). I wouldn’t…

Updated: May 10th, 2009

Slave delay can be a nightmare. I battle it every day and know plenty of people who curse the serialization problem of replication. For those who are not familiar with it, replication on MySQL slaves runs commands in series – one by one, while the master may run them in parallel. This fact usually causes bottlenecks. Consider these 2 examples:

• Between 1 and 100 UPDATE queries are constantly running

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Updated: September 5th, 2008

So Google Chrome – Google's attempt at an open source browser, came out yesterday and I took it out for a spin. At its heart is the Webkit engine (also open source) and Google Gears, powered by SQLite (can MySQL rival SQLite in applications like this?). Here are my thoughts.

• Fast – Chrome

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Man, this video hits too close to home. Developers all over the world are in pain, so go ahead – hug one right now! Dedicated to all developers at blinkx, MySQL, and beyond.

Updated: August 28th, 2008

Newsflash: Perl 6 is not dead (in case you thought it was)!

I stumbled upon this most excellent series of posts by Moritz Lenz of perlgeek.de that describe the differences between Perl 5 and the upcoming Perl 6 (thanks to Andy Lester for the link). The posts are done in the form of tutorials, which helps comprehension. Simply awesome, Moritz.

It seems like Perl…

According to Wikipedia, in April 2008, the number of videos on Youtube was 83.4 million (ref: http://en.wikipedia.org/wiki/YouTube#cite_note-5). However, the link in the cite note now displays “*” video results 1 – 20 of millions, without showing the real count.

Here's one way I found to get an estimated, but relatively accurate, number of videos on the popular video sharing site Youtube….