I delivered a session on graph databases, and in it I used RedisGraph to show how you can work with graph data on that platform. This blog shows a basic creation of a graph in RedisGraph. This isn’t intended to be a comprehensive post, but more a basic look at the code to work with graphs.
Adding Data
I connect to Redis with the command line. If you don’t know how to do that, I covered this in another post. Once I’m connected, I can run this code to create a graph and a node:
GRAPH.QUERY Northwind "CREATE (:employee {employeeID: 10, firstName:'Steve', title:'President'})-[:REPORTS_TO]->(:employee {employeeID: 11, firstName:'Tia', title:'CEO'})"
This will create a graph, two nodes, and one edge between them. This starts with GRAPH.QUERY, which let’s Redis know this is a graph query. I then give the name of the graph, which is Northwind since I based this on the Northwind dataset.
Next I use a Cyper language CREATE and enter the data in what is very similar to JSON. I label a node (employee), add the properties and values (employeeID and firstName with 10 and Steve as values).
I use the square brackets with the edge name in between this and another node. This will get me the results shown below. You can see that one label, two nodes, six properties, and 1 relationship created.
I can get the employee nodes with this code:
GRAPH.QUERY Northwind "MATCH (e:employee ) return e"
This returns the two nodes.
If I want to see the relationship, I need to ask for that with this code:
GRAPH.QUERY Northwind "MATCH (e:employee)<-[:REPORTS_TO]-(sub) RETURN sub.firstName as employee, e.firstName as manager"
This returns my graph as a series of data elements.
Tada!
There is more you can do and certainly you can create more complex (or larger) graphs in Redis. The drivers from various languages should return JSON to you that you can deserialize and visualize or otherwise process results.
A lot of this is basic, but if you want to experiment with Redisgraph, a container and the CLI is a good way to get started.
