FS vs. DBMS

19.2.10

The other day I was attending a talk by UCSD Professor Charles Elkan about the Netflix competition, who was incidentally one of two external judges of it, which was really insightful and started getting me interested in Data Mining. So after thinking about storage requirements for my pet-‘Web 4.0 monolithic web-application’ I decided to dig deeper into DBMS technology vs. filesystems. I learned about OODBMS along the way, so we have to cover those briefly as well.

Let’s start with DBMS. They were created to handle large sets of data efficiently in the face of lots of concurrent reads and writes – read users – as well as allow swift querying of that data. They evolved from a mathematical sound theory – first order predicate logic – into what is known as relational algebra. To summarize, DBMS provide the following things:

  • Correctness under concurrent access – known as the ACID principles,
  • Complete indices for the data which together with
  • a querying language based on a mathematically closed model allows for efficient searching aka. a powerful query execution engine.

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Adium/Pidgin skype plugin

18.2.09
Adium
Image via Wikipedia

Some time ago I installed Nimbuzz on my iPhone and found it very cool. It allows connection to the chat systems of MySpace and Facebook and even StudiVZ – the german FB copycat that is being sued for stealing from FB – and I didn’t even know they had a chat system. Turns out they do and lots of people are requesting some kind of plugin for it, but despite talk about them opening up their API all over the net, they have not done it yet.

So naturally, I got curious how they do it and started digging. Turns out that they have a deal with SVZ which gives them access to their API. It also turns out that Nimbuzz works by running an OpenFire gateway from Jabber/XMPP to all the other IMs on their server. OpenFire is free and comes with plugins for all major IMs except skype and SVZ which they must have added. This makes sense since they only have implement the XMPP proto in their mobile client instead of all of them, and then use the GW for all accounts.

So by using a Jabber client and connecting to the nimbuzz server (on snow.nimbuzz.com) with your account you can use their GW. So I tried connecting with my Adium. Using the SVZ GW works like it should, only drawback is that Adium does not understand the msg to rename the contact. The skype gw also works but only gives you your buddies presence notifications when you send a special msg that pretends to be the iPhone client. Not even the web or Windows nimbuzz client can use the skype gw. Still that was not enough for me, so I looked again the Pidgin skype pluging that I had found a while ago and not found interesting, because it does not silence skype. You have to have skype running in the background to use their API and access their p2p net. But if you get a msg from a buddy skype still opens a chat window and notifies you, alongside Adium. That was very annoying, so I stopped using it. The newer version however, does succeed in silencing skype in the bg so that it won’t notify you anymore, so it is very useful. You can find it here: http://eion.robbmob.com/. It even gets status msgs and profile pix from your buddies which the nimbuzz gw doesn’t. Along the way I also found a very interesting presentation about dissecting skype and its proto here: http://tinyurl.com/zkuww.

I won’t bother with skype anymore but I will attempt to write an Adium plugin for the nimbuzz SVZ gw that sets the real nicks and also gets their pics.

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