Neo4j - Cypher vs Gremlin query language

Question

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.

Answer 1

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.

Answer 2

We have to traverse thousands of nodes in our queries. Cypher was slow. Neo4j team told us that implementing our algorithm directly against the Java API would be 100-200 times faster. We did so and got easily factor 60 out of it. As of now we have no single Cypher query in our system due to lack of confidence. Easy Cypher queries are easy to write in Java, complex queries won't perform. The problem is when you have multiple conditions in your query there is no way in Cypher to tell in which order to perform the traversals. So your cypher query may go wild into the graph in a wrong direction first. I have not done much with Gremlin, but I could imagine you get much more execution control with Gremlin.