March 7th, 2012 at 10:37pm
In today’s Clojure meetup Stefan Hübner gave an introduction to Cascalog - a Clojure library based on Cascading for large scale data processing on Apache Hadoop without hassle.
After a brief overview of what he is using the tool for to do log processing at his day job for http://maps.nokia.com Stefan went into some more detail on why he chose Cascalog over other project that provide abstraction layers on top of Hadoop’s plain map/reduce library: Both Pig and Hive provide easy to learn SQL-like languages to quickly write analysis jobs. The major disadvantage however comes when in need for domain specific operators - in particular when these turn out to be needed just once: Developers end up switching back and forth between e.g. Pig Latin and Java code to accomplish their analysis need. These kinds of one-off analysis tasks are exactly where Cascalog shines: No need to leave the Clojure context, just program your map/reduce jobs on a very high level (Cascalog itself is quite similar to datalog in syntax which makes it easy to read and simple to forget about all the nitty-gritty details of writing map/reduce jobs).
Writing a join to compute persons’ age and gender from a trivial data model is as simple as typing:
;; Persons' age and gender
[?person ?age ?gender]
(age ?person ?age)
(gender ?person ?gender)
Multiple sorts of input generators are implemented already: Reading text files, using files in HDFS as input are both common use cases. Of course it is possible to provide your own implementation for that as well to integrate any type of data input in addition to what is available already.
In my view Cascalog combines the speed of development that was brought by Pig and Hive with the flexibility of being able to seemlessly switch to a powerful programming language for anything custom. If you yourself have been using or even contributing to either Cascalog or Cascading: I’d love to see your submission to Berlin Buzzwords - remember, the submission deadline is this week on Sunday *MEZ*.
March 7th, 2012 at 7:39pm
There are literally hundreds of bars and restaurants in easy walking distance to the conference venue. And if that is now enough for you, hop on U-Bahn and head east to either Kreuzberg or Friedrichshain to find more. For inspiration check out Tip Berlin - they have a decent, reliable restaurant list.
For quick orientation: Berlin is no one city center but many districts that all have their own look and feel to them. Those most interesting for eating and drinking:
- Schöneberg is a bit more calm, well suited for eating out until late evening. The two areas that are most interesting are around Akazien-/Golzstr (head north from Hauptstraße up until Nollendorfplatz), Crellestraße, as well as the area around Bayrischer Platz.
- Friedrichshain is the area to go for drinks in the evening and to see the young, urban Berlin. Get lost in the famous “Simon-Dach” quarter (”Simon-Dach-Kiez” as we say in Berlin) with its cobble stone streets, wide sidewalks, bars, restaurants and cool little shops. If the weather is as nice as it has been on the weekend, it might be worth walking or cycling a little farther to Holzmarktstraße. Between the streets “An der Schillingbrücke” and “Michaeliskirchstr.” (see http://bit.ly/cNqLZq) there are a few really nice outdoor beach bars right on the banks of the River Spree.
- Kreuzberg comes in at least two flavours: For coffee and food head over to Bergmannstraße, for drinks at night go see Oranienstraße, for young and vibrant head over to Wrangelstrasse (do not miss Heinz Minki, Freischwimmer and Club der Visionäre), for a relaxed “down by the river” evening head over to Maybachufer (do not miss Van Loon, also check out Bethanien close by).
- Prenzlauer Berg - young, family friendly, slowly being turned into a German Kleinstadt
- Mitte - a bit more fancy, gentrified, great if you love culture, museums, ballet, concerts. Remember to explore the city by boat. If you are hungry head over to Linienstrasse and explore the little streets around. There is tasty cheese fondue available at Nolas am Weinberg. Go dance at Clärchens Ballhaus, get a coffee and code while drinking at web2.0 cafe Sankt Oberholz.
Two special recommendations for breakfast:
On the weekend before the conference days are best started with a long and tasty brunch. My personal recommendation if you love tea is to head down to TTT - apart from serving best tea in town you can also get really tasty food there. And best of all, buy tea, tea cups and pots. I tend to take keynote speakers to that place - so far none has complained
Another option is to start your day on top of Bundestag - enjoy the view of the city, take an audio, tour, eat breakfast in the Käfer Restaurant and maybe add a brief lecture on German legislation afterwards. Make sure to book about a month in advance!
For burgers there is no better place than Burgermeister in Kreuzberg. Best Falafel is on sale at Habibi. Judging on where to get the best ice cream actually is a bit harder: Aldemir is the location in Kreuzberg, Pinguin Club is the location in Schöneberg (Inka Eis beats that only if you are more for unusual types of ice cream), if you are in Mitte close to Brandenburger Tor consider visiting Der Eisladen - lots of different types and really tasty.
When it comes to cocktails there are various locations - large and small that people tend to frequent. Some places to start and feel welcome: Salut, Green Door and Stagger Lee.
Relocating to Berlin
March 6th, 2012 at 6:27pm
Ever made the mistake of booking a flight to a city and trying to decide on what to do only after you arrived? That type of planning does work for Berlin - though you may end up with quite a different schedule than originally intended.
The only thing that needs a bit of planning ahead (about a month) is visiting the Bundestag - fast way to discover it is to just go up to it’s dome. You can book a table at the restaurant up there if you want to have breakfast above Berlin. In addition the visitor service offers various presentations for free that can be booked from their web page.
Some hints in addition to visiting a tourist information after your arrival:
When I have guests I usually recommend to either buy a day (or week) BVG ticket - you can use public transport as often as you like with these tickets. That includes S-Bahn, tram, busses, tube and ferries (but not the tourist roundtrip boats with moderation). If you know you’ll be going to several museums, a Welcome ticket might be worth it’s prize. Alternatively just get a bike - unless you want to reach destinations outside the s-bahn-ring or want to visit in winter (don’t) all distances should be easy to do by bike. To plan your trips use bbbike.de - they know road conditions to e.g. let you exclude larger streets or prefer green routes.
Your best bet to see most of the attractions for less than five Euro is to take the regular bus line 100 from the Bhf. Zoo train station down to Alexanderplatz and line 200 back. Though no audio guide is known to me there should be guides available for sale in local tourist information offices.
For guide books: Lonely Planet is a good start. If you speak German the city box might serve you well. It contains 30 cards with proposed walking tours including brief explanations. Also the book “Die schönsten Berliner Stadtspaziergänge” has been great to discover areas that are less known.
The city has two bi-weekly magazines that feature lists of concerts (both modern and classical), exhibitions, markets and more: For one there is Zitty, the other one Tip Berlin. Both are quite good, which one to prefer depends on personal taste. In addition both publish restaurant guides, books on where to go shopping, special issues on where to go and what to do. In addition their online restaurant reviews are quite decent.
Two final hints: If you happen to know locals (or anyone who moved their a while ago) - make sure to ask them for recommendations. Also, try to stay at one of the many B&B locations - in general you host will know several local recommendations.
Relocating to Berlin
March 2nd, 2012 at 8:08pm