A powerful less-known function on Facebook – The Graph Search


As an expat I continuously use Facebook to network and to meet up with friends. Whenever I travel to a new city, I check first whether any of my friends live there. Graph Search allows me to gather this information. It is still in beta, therefore it needs to activated here and the language should be changed to English (US). It does not work from the mobile application, only from the desktop web site.

For example a simple query can be formulated this way to find out who is living in Berlin:

My friends who live in Berlin, Germany

N.B.: Feel free to use the autocomplete or suggestions. The TAB key can also help.

Or maybe it is worth to get some tips from the buddies of my friends:

My friends of friends who live in Berlin, Germany

Also there are some nice activities in the city, that my friends attend. Let us check it out:

Events iBerlin, Germany that my friends will attend

Any good places to eat out? Let Facebook answer this question.

Restaurants in Berlin, Germany that my friends like

However Graph Search can be also used to gather more information about your friends. I do not recommend to fully trust this, because things happen in the real life. Some examples:

What kind of pictures a friend likes:

Photos that János Binder likes

Which girls are interested in liking my photos. Maybe it is time to poke them :) :

Females that like my photos

Photos that “my friends of interest”* likes – Replace the name with your friends name

List the photos that I posted in 2014.

Photos in 2014 that János Binder posted

What kind of event do I attend, what kind of music I like:

Events that János Binder attended

Music that János Binder likes

At last, but not at least, some fun with Graph Search :)

More examples: More clever uses

P.S.: There are some differences between various nationalities. For example Graph Search works pretty well on my Hungarian friends, because they share way more information on Facebook that my German friends.


A SofortÜberweisung “feature” – cancelling transactions without noticing the merchant

During the past years a new company, called SOFORT AG, wants to introduce a new way of payments. It offers a product called SofortÜberweisung, which provides way lower fees than normal credit cards transfer and the merchant can be “pretty sure”, that (s)he receives the payments. It works the following way: The customer is redirected to the SOFORT AG’s website, where (s)he is requested to enter the banking details to carry out a wire transfer. (Through a standard interface in Germany based on FinTS/HBCI protocol.) After making sure that the customer has enough credit on the account and the transfer has been accepted by the bank, the merchant gets a confirmation about the transaction.

A graphical overview about the functionality of Sofortüberweisung. Taken from: https://de.wikipedia.org/wiki/Sofortüberweisung


However here comes the trick, accepting and executing a transaction are two different things. This means that the wire transfers can be cancelled after ordering the product, however the merchant is not notified. One bank, where such cancellation is possible is the HypoVereinsbank. I am pretty sure that other banks also allow this, however I have not had the time to test them. Unfortunately I have not found any information about this on SOFORT AG’s website and many merchants are not aware that there is a chance that the payment will never arrive. (Update: Meanwhile I had a call with SOFORT AG, and I was told that the merchants are informed about this possibility in the contract and they have an “insurance package” against cases like this.)

The possibility of cancelling SofortÜberweisung transaction using the “löschen” button.

This possibility allows misuse of the SofortÜberweisung systems and the merchants can be betrayed up to a several thousand of Euros. (Some possible examples: imagine converting currency at TransferWise or getting first class tickets at Lufthansa, without payment.)

Although such misuse happens very rarely, I strongly advise the merchants to hold back the product (especially expensive products) until the wire transfer has been credited on the account.


Internet telephone software providers and softwares

It is very convenient to have an internet telephone account as an expat, because calling a land line is around 1-2 eurocent/minute and one can have a dedicated phone number, that one can bring easily to a new country. I prefer to use standardised solutions (such as SIP), because there are more software and specialised hardwares available and I am not locked to one company. Two providers those I use:

Neophone – Pro: European and USA landlines around – 1,7-2 eurocents/minute, Mobiles 12-17 eurocents/minute, pay per second Con: basic user interface, can be charged only with Hungarian credit card

Sipgate – Pro: German phone number with proper area code (e.g. having a prefix from Berlin, but it rings in Hungary), user friendly and professional interface Con: pay per minute, calling Hungary costs twice as much than Neophone.

User agents (softwares) to call:

Media5-fone (iOS, Android) – Pro: very powerful and very stable Con: have to pay to remove the ads, the user interface seems a bit clumsy.

Telephone (Mac) – Pro: free and open source app with an user-friendly interface


Experiment: having data-only mobile subscription

Being a heavy smart phone user I decided to sign up for for a data-based subscription where every extra SMS and calls are charged. I found a nice offer where 10 GB per month is included for roughly 69 DKK/month (~10 €) in Denmark, and that so far satisfies almost all of my needs. Also checking the monthly bills, I am familiar with my calling habits, therefore it would not be worth to have some hundred minutes included the package.

Unfortunately such offer does not exists in Germany and most of the subscriptions are limited to 200MB-1Gb of traffic. Also the mobile providers are still trapped with the so called “Flat-Rate-Fetish”, which means that the customer can call multiple mobile/landline networks freely depending how much they pay. This option was popular roughly a decade ago, however the providers failed to follow the changes. Even worse for example: Deutsche Telekom’s Hungarian subsidiary company has packages ranging between 100Mb-26Gb (for ~3-33€/month), but for some reason these successful options are not offered in Germany.

Creating self-updating databases in bioinformatics

We have combined multiple data sources in the project that I am working on and we wanted to make sure that whenever a new release of the source database is out it should be incorporated automatically. Thus we avoid the hassle of updating every year our service, so I think putting more time in setting up the pipeline is a worth investment. Therefore I provide a draft, how that pipeline can look like:


# Change to correct working directory.
cd ...

# Download UniProtKB if necessary.
wget -N ftp://ftp.uniprot.org/pub/databases/uniprot/current_release/knowledgebase/complete/uniprot_sprot.dat.gz


# Run make to update files as needed.
make all

# Import new tagging results into database.
../pgsql/bin/psql ...
rm database_*.tsv

The update script is a simple bash shell script. First it changes to the directory where the scripts and data files are located. The reason the script is usually scheduled to be launched by crontab and the working directory should be specified.

Afterwards wget with flag –N downloads the database only if it has been updated. Then make will check whether any of the databases have been changed and it will compile those targets which are dependent on the newer data sources.

The last part of the script takes care of the export to a SQL server. Calling a perl script it prepares a tab separated value file for PostgreSQL, and then the file will be imported in the database. Finally the temporary files are cleaned up.