I'm starting to develop with Neo4j using the REST API. I saw that there are two options for performing complex queries - Cypher (Neo4j's query language) and Gremlin (the general purpose graph query/traversal language).
Here's what I want to know - is there any query or operation that can be done by using Gremlin and can't be done with Cypher? or vice versa?
Cypher seems much more clear to me than Gremlin, and in general it seems that the guys in Neo4j are going with Cypher. But - if Cypher is limited compared to Gremlin - I would really like to know that in advance.
For general querying, Cypher is enough and is probably faster. The advantage of Gremlin over Cypher is when you get into high level traversing. In Gremlin, you can better define the exact traversal pattern (or your own algorithms) whereas in Cypher the engine tries to find the best traversing solution itself.
I personally use Cypher because of its simplicity and, to date, I have not had any situations where I had to use Gremlin (except working with Gremlin graphML import/export functions). I expect, however, that even if i would need to use Gremlin, I would do so for a specific query I would find on the net and never come back to again.
You can always learn Cypher really fast (in days) and then continue with the (longer-run) general Gremlin.