Database Reference
In-Depth Information
Table 9.1 Graph database model comparison
Entity
Relation
Visualization
Complex
Dynamic
Nested
Neighborhood
Hypernode
+
+
+
+
+
Groovy
+
+
+
+
GGL
+
+
+
+
GOOD
+
+
GMOD
+
+
PaMaL
+
+
+
+/
GDM
+
+
+
LDM
+
+
Social Network is an explicit representation of relationships between people,
groups, organizations, computers, or other entities [
9
]. As other networks, it can
be represented as a complex graph [
2
],
G
(
V, E
), where
V
is the set of nodes
representing people and
E
is the set of edges (
V
¼
V
) meaning the different kind of
relationships among people.
Indeed, the social network structure can contain one or more types of relations,
one or more types or levels of entities, and many attributes over the entities. This
structure is dynamic due to growth of the volume, change of attributes, and
relations.
Then, we compare the previous graph database models using some character-
istics related to social network: the ability to present dynamic and complex objects,
nested and neighborhood relations, and the ability to give a good visualization of
social network. We resume the comparison on Table
9.1
, where “+” indicates the
graph model support, “
”
partial support. From this comparison, we have concluded that models based on
hypernodes can be very appropriate to represent complex and dynamic objects. In
particular, the hypernode model with its nested graphs can provide an efficient
support to represent every real-world object as a separate database entity. More-
over, models based on a simple graph are unsuitable for complex networks where
entities have many attributes and multiple relations.
” indicates that the graph model does not support, and “+/
9.2.2 Graph Database Languages
A query language is a collection of operators or inference rules, which can be
applied to any valid instance of the model data structure types, with the objective of
manipulating and querying data in those structures in any desired combination [
10
].
In this section, we review some proposals for graph database query languages found
in the literature. We concentrate this study on visual, semantic, SQL-like, and
formal query languages.
Search WWH ::
Custom Search