Querying the paths

A path here consists of an anchor node or starting node and traverses one or more hops in any direction from it. In the earlier section, we worked with the Patient node to showcase how to query nodes. Here, let us start from the Patient node and what it is connected to at one hop.

Our Cypher query can look as follows:

MATCH path=
   (:Patient {id:'7361ce15-cf67-ae76-88e6-bcbdca19ce0b'})-->()
RETURN path

This returns all the paths in one hop in the outgoing direction from the Patient node:

Figure 4.20 – All paths one hop from a patient

Here, we can see one Race node, one Ethnicity node, and 60 Encounter nodes. Say that we want to find out the race demographics of our patients where we can use paths to get these values. The Cypher query for it will look as follows:

MATCH (r:Race)
RETURN r.type as type, size((r)<-[:HAS_RACE]-()) as count

This query retrieves all the Race nodes and returns...