Today I wanted to add the PHP EXIF extension to my local PHP installation. According to the PHP manual to do this you should configure PHP with –enable-exif. However, I didn’t want to go through the tedious process of compiling PHP from scratch again. I just wanted to add the single extension.
I couldn’t find any info on how to do this, but thankfully it is actually quite simple, it’s pretty much the same as compiling any extension that doesn’t come with PHP as standard. This same process should work with any of the extensions that ship with PHP.
I’m not particularly knowledgable on the subject of optimising SQL queries, so the easiest way to optimise a query for me is to write a few variations then test them against one another. To this end I’ve developed a PHP class to do the testing and benchmarking. I think that even if I was highly knowledgable about optimising queries, then I would still want to test my queries to ensure that my theory held true in practice.
For a useful benchmark you need to execute the queries using a range of data that simulates the real data the queries would be executed with. They also need to be executed in a random order and multiple times, to ensure results can be averaged and reasonably reliable. That’s what this class does, along with providing a summary of the results in CSV format.
It should be noted that this class does not set up or modify any tables for testing with – it just allows you to supply a range of data to be included within the queries themselves, such as testing with a range of different values in a WHERE clause.
Okay, I doubt this post will be useful to anyone else, but I thought I might as well post it since I haven’t updated this blog in a while.
On ‘my’ web server I have some sites that are served by a shared Apache process. This stores daily logs, for one week, rotating the log numbering each day. I have a cron job that runs once a week and concatenates the past week’s logs into a single file, which is then stored elsewhere.
Today I was trying to run awstats to generate stats from the last months worth of logs (I check my sites stats once every month). However, I realised that my cron job was concatenating the daily logs into the weekly log file in the wrong order. This resulted in awstats only picking up the first day from each weekly log, as the rest of the log file had requests with earlier timestamps. It seems that awstats works through the log file chronologically.
So, to get my stats I had to re-order the log files so that the entries were listed chronologically as they should be. To do this I decided to use PHP, mostly just because that is the language I am most familiar with.