  In this paper, we propose a compact data structure to store labeled
attributed graphs based on the k2-tree, which is a very compact data structure
designed to represent a simple directed graph. The idea we propose can be seen
as an extension of the k2-tree to support property graphs. In addition to the
static approach, we also propose a dynamic version of the storage
representation, which allows exible schemas and insertion or deletion of data.
We provide an implementation of a basic set of operations, which can be
combined to form complex queries over these graphs with attributes. We evaluate
the performance of our proposal with existing graph database systems and prove
that our compact attributed graph representation obtains also competitive time
results.
