The full power of graph databases, and Neo4j in particular, lies in their ability to go from one node to another by following relationships in a super-fast way. In this section, we explain how to read data from Neo4j through pattern matching and hence take full advantage of the graph structure.
Pattern matching
Let's take the following query:
MATCH ()-[r]-()
RETURN r
When we write these kinds of queries, we are actually performing what is called pattern matching with graph databases. The following schema explains this concept:
In this scenario, we have a directed graph made of nodes with labels A or B. We are looking for the sequence A -> B. Pattern matching consists of moving a stencil along the graph and seeing which pairs of nodes and relationships are consistent with it. On the first iteration, both the node labels and the relationship direction matches the search pattern. But on the second and third iterations, the node labels are not the...
