The RavenDB client API is built with the notion of layers. At the top, and what you will usually interact with, are the DocumentStore and the DocumentSession.
They in turn, are built on top of the notion of Operations and Commands.
Operations are an encapsulation of a set of low level commands which are used to manipulate data, execute administrative tasks, and change the configuration on a server.
They are available in the DocumentStore under the Operations, Maintenance, and Maintenance.Server properties.
Common operations include set based operations for Patching or removal of documents by using queries (more can be read here).
There is also the ability to handle distributed Compare Exchange operations and manage Attachments.
How to Send an Operation
In order to excecute an operation, you will need to use the Send or SendAsync methods. Avaliable overloads are:
var getBuildNumberResult = documentStore.Maintenance.Server.Send(new GetBuildNumberOperation());
var buildNumber = await documentStore.Maintenance.Server.SendAsync(new GetBuildNumberOperation());
By default, operations available in store.Operations or store.Maintenance are working on a default database that was setup for that store. To switch operations to a different database that is available on that server use the ForDatabase method.