Security. Instead of using tables "Roles, Users, UserRoles, Actions, RoleActions" or whatever model you've come up with in the past, think in terms of graphs:

Security. Instead of using tables "Roles, Users, UserRoles, Actions, RoleActions" or whatever model you've come up with in the past, think in terms of graphs: Person P [IS IN] Role R Action A [IS IN] Role R Now you can match a person to actions and using a query language like Cypher (Neo4J), it's very easy. I've found this to be vastly more efficient than using a relational or document database. I have an implementation of Identity Server 3 with the back end store in Neo4J and it's so much easier than managing a SQL back end.