Modeling Data in MongoDB vs ArangoDB

05Architecture, Documentation, Graphs, Query LanguageTags: ,

MongoDB is a document DB whereas ArangoDB is a multi-model DB supporting documents, graphs and key/values within a single database. When it comes to data modeling and data querying, they pursue somewhat different approaches.

In a Nutshell: In MongoDB, data modeling is “aggregate-oriented”, avoiding relations and joins. On the other side, everybody has probably used relational databases which organize the data in tables with relations and try to avoid as much redundancy as possible. Both approaches have their pros and cons. ArangoDB is somewhat in-between: You can both model and query your data in a “relational way” but also in an “aggregate-oriented way”, depending on your use case. ArangoDB offers joins, nesting of sub-documents and multi-collection graphs. More info

CAP & Google Spanner: the survival of eventual consistency – A response to Dave Rosenthal’s article on Gigaom –

06Future-of-nosqlTags: ,

In Next gen NoSQL: The demise of eventual consistency a recent post on Gigaom FoundationDB founder Dave Rosenthal proclaims the demise of eventual consistency. He argues that Google Spanner “demonstrates the falsity of a trade-off between strong consistency and high availability”. In this article I show that Google Spanner does not disprove CAP, but rather chooses one of many possible compromises between total consistency and total availability. For organizations with a less potent infrastructure than Google other compromises might be more suitable, and therefore eventual consistency is still a very good idea, even for future generations of nosql databases.

More info

ArangoDB at FOSDEM 2014

00General, PresentationTags: , ,

FOSDEM is an absolutely open and free conference in Brussels, Belgium. The conference offers an impressive amount of developer rooms discussing a broad range of technical topics, including NoSQL and graphs.

After a funny and productive ArangoDB hackathon weekend Frank and I arrived at FOSDEM on Sunday noon. We were looking forward to the talks in the graph devroom, but unfortunately for us it was not possible to enter the room (it was overfull, indicating a great quality of talks).
At the next speakers change Frank and I managed to slip into the room and could enjoy two inspiring talks by Neo4J.
Afterwards it was my turn to present the graph visualization interface in ArangoDB in a still crowded room (slides).
After my presentation, we handed out all our ArangoDB t-shirts to our fans.

Michael handing out T-Shirts to the audience

Michael handing out T-Shirts to the audience

All together it was a great experience and a really huge amount of people visiting the same conference which impressed me a lot.
Thanks for the team at the Graph Processing devroom for giving me the opportunity to speak and for organizing such a great devroom.
We will meet again next year.

so long,

ArangoDB goes Barcelona – NoSQL matters 2013

00GeneralTags: ,

The ArangoDB team traveled to Barcelona for the “NoSQL matters” – weekend. Day one was packed with a lot of NoSQL-trainings and Jan introduced the NoSQL landscape by explaining how to model your data in a non-relational world. Following the wish of many participants Jan had to repeat the morning session about the new and exciting possibilities of NoSQL in the afternoon.

After an inspiring key-note by Nathan Marz, three tracks full of NoSQL, BigData and Searching explained the latest trends.


Lucas talked about ArangoDB in general, Foxx and the advantages of multi-models. He explained “why relations — especially properties graphs — matter even in a NoSQL database” by Sarahs Mei’s example of social networks.

After his talk, we had a lot of interesting and inspiring discussions at the ArangoDB booth in the entry hall.


NoSQL matters was a great experience for us, which gave the ArangoDB team the opportunity to meet a lot of interesting people to exchange and to develop new ideas.

(German video) Nosql meets

03PresentationTags: ,

Last week Jan (core member of ArangoDB and the brain behind AQL and many other parts) was invited by “” – a user group here in Cologne dealing with mobile development.

In this talk Jan gives a general overview on nosql databases and the different flavors. He explains how to query a nosql database and he evaluates how a nosql database can be used in a mobile app.

Warning: The talk is in German. If you want to hear it in English, let us know in the comments. 🙂

“NoSQL meets” by Jan Steemann.

“Use-Cases for MRuby in a Database like ArangoDB” or “Can MRuby be the next PL/SQL?”

00RubyTags: ,

In the relational world, PL/SQL is used to store business/application logic inside the relational database. The same movement is currently happening in the NoSQL. Redis for example uses LUA script in its newest version (2.6), to allow developers to tweak Redis. There a lot of use-cases for a programming language in document-stores. Programming languages are used in various document stores like ArangoDB, CouchDB, MongoDB, or VoltDB. In my opinion in the following use-cases a suitable language like Ruby will be most handy.
More info

RFC – The ArangoDB/AvocadoDB query language

02Query LanguageTags: ,
Note: We changed the name of the database in May 2012. AvocadoDB is now called ArangoDB.

The REST API for AvocadoDB is already available and stable and people are writing APIs using it. Awesome. As AvocacoDB offers more complex data structures like graphs and lists REST is not enough. We implemented a first version of a query language some time ago which is very similar to SQL and UNQL.
More info