History[02][04]

ArangoDB was ready to be used in production since version 1.0 released in spring 2012. The current version is 3.4.0.

Concurrency Control

Data Model[05]

In ArangoDB, a document collection always has a primary key _key. Therefore, without specifying any secondary index, it is just like a key-value store. Generally, there can be multiple attributes and multiple secondary indexes, then it is like a common document store. By default, the sharding key is the same as the primary key _key. Therefore it can achieve good linear scalability. Besides key-value store and document store, ArangoDB can also support graph store with comprehensive functionalities.

Indexes[06]

By default, the index of a document is a hash index on its _key attribute. At the same time, user can specify other indexes including skip list, fulltext index, persistent index, geo-spatial Index etc.

Logging[07][05]

ArangoDB does not overwrite existing documents. Instead, it create a new version of modified documents for all the write operations (including delete operation). ArangoDB's Write-Ahead-Logging records all these write operations that were executed on the server.

Query Interface[08]

ArangoDB has its own query language ArangoDB query language (AQL). AQL queries can be invoked using Arangosh (ArangoDB Shell), web interface, or HTTP REST API.

Storage Architecture[04]

ArangoDB is a mostly-memory database.

Storage Organization