For user projections (which queries are, under the hood), you need to start the Event Store with --run-projections=all from the command line (or an equivalent method such as in the JSON config files/environment variables depending on how you prefer to
configure your machine as listed here https://github.com/eventstore/eventstore/wiki/Command-Line-Arguments ). Your actually query looks fine. There are also some standard projections
which you need to enable for certain features of the DSL (such as fromCategory).
However, if you’re investigating queries and projections I’d strongly recommend using a more recent build, you can get the RC of v3 of Event Store from http://ha.geteventstore.com/showcase/EventStore-NET-v3.0.0rc1.zip
- there are a few issues to iron out in Linux prior to releasing it however. There are many fixes to queries and projections in particular in this build.