Suchergebnisse mit Tag „Perl“
I recently started my first Dancer & MongoDB project. MongoDB is my preferred database (at the moment) and Dancer is a great framework, but something is missing: I really prefer using an ORM and didn't find anything for MongoDB which fits my needs.
Did you find a typo in the title? No? You're right. I recently started to love the Perl Dancer Framework - and tried to write my first cronjob for a Dancer based project today.
Look at the title and you're done. No need to add a text to this post if everything is said in the title. Not really? France is too small to hold half of the world's population? No way! My computer told me that 4.294.967.296 people live in France - and computers don't fail, you know?
Some weeks ago, I wrote a post about aggregated logging by merging many "UPDATE ... SET count=count+1" SQL statements into one. But there's a problem: All of the data stored in memory is lost if the task or server crashes or if the database dies and doesn't come back until the task exists. Here is how I solved this problem.
Most people would answer "on top of my neck" but that's not always right. Actually, most heads are above their bodies but not every head has a body - which usually is no problem. Trouble starts when someone asks for a head without a body. Headhunters do (but I don't care about them, at least within this post) and web-browsers also do from time to time.
A co-worker asked recently me asked me: "Isn't Perl dead?" It isn't, many people and companies are using it, but no one talks about it.
Statistics are nice, but may also increase database load. Counting web users (page impressions) may produce a lot of UPDATE requests setting counter=counter+1. I tried to merge them using Gearman.
Vor einiger Zeit war ich auf der YAPC::EU 2012. Einige Talks wurden dort aufgezeichnet und endlich sind die Videos online- wenn auch leider von weniger Talks als erhofft. Hier sind meine Favoriten.
I visited YAPC::EU 2012 this year and some of the talks have been recorded. Finally, the recordings are online - much less than I expected, but here are my favorites out of them.
Perl doesn't care about numbers, integer or float - at least on the script level - but MongoDB does. The driver's default number detection algorithm treats floats as strings and MongoDB doesn't like to compare strings with less-than or greater-than operations.
Database load, disk, CPU and memory usage are known ressources on modern servers, but there is another one which is much more important: The I/O volume is limited and can't be raised as easy as all the others. It has no fixed limit and can't be measured (very good). It's a rare (maybe the most rare) good and shouldn't be wasted.
Warnings aren't useless, they may be hints to invisible problems - which could become "big trouble" lateron. Recently, I was trying to track down a warning which didn't make any sense.
Ich nutze MongoDB schon seit über einem Jahr, bisher aber nur für kleinere Sachen - und ohne MapReduce. Dabei ist es genau diese Funktion, die viel zur Macht dieser ungewöhnlichen Datenbank beiträgt.
I recently decided to prefer MongoDB for new projects and it turned out that I still need to learn a lot of things about it. One of them is MapReduce which is more powerful than (most) SQL SELECT options.
Someone asked me about a CRC32B checksum today. No problem, there is CPAN and a common checksum like CRC should be very easy, there must be a module (or two or three or so) on CPAN, task done, next one. Stop. There are two modules for CRC32: Digest::CRC32 and String::CRC32 but really nothing for CRC32B.
I tried to set up a little notification daemon in one of my projects: It should send a message to my GoogleTalk account for special events and that should be easy using one of the huge amount of Jabber/XMPP modules on CPAN.
I wrote about Gearman some time ago and didn't get the tuits to write the next posts, but here we go: How to start working with Gearman.
I strongly suggest that you don't start by adding Gearman to your productional systems because there are many things to consider and you probably don't want to rewrite everything once it's running.
Azawawi introduced his newest tool to the #Padre channel today: Farabi, a web-based Perl editor/interpreter/everything.
Todays world is UTF-8, I'm very sure that most software worldwide is UTF-8 today but mySQL on Perl?
Encoding is fun. A shirt stating "Schei? encoding" is very popular among German developers. My boss discovered a bad encoding problem yesterday and we've been spending hours searching for the reasons and a solution.
I need to encode and decode a complete hash tree (a value which might be a reference which might contain other references which might contain other references which...) and there is no "Encode::Tree" or "Hash::Encode" module on CPAN.
Every single line of source code is being tested very deeply before being committed, isn't it? Well, maybe in a perfect world but reality has very little space for testing your source and simple typos often break stuff unnecessarily. Developers usually don't like testing at all, they want to develop new stuff and finish annoying tasks as fast as possible.
