A path expression (or simply a path) represents a set of values that are reachable when traversing a given sequence of links or properties from some source set.
The result of a path expression depends on whether it terminates with a link or property reference.
if a path does not end with a property reference, then it represents a unique set of objects reachable from the set at the root of the path;
if a path does end with a property reference, then it represents a list of property values for every element in the unique set of objects reachable from the set at the root of the path.
The syntactic form of a path is:
expression path-step [ path-step ... ] where path-step is: step-direction pointer-name
The individual path components are:
Any valid expression.
It can be one of the following:
. for an outgoing link reference
.< for an incoming or backlink
@ for a link property reference
This must be a valid link or link property name.