Gremlin

The Graph query transform and the Graph script action run Gremlin traversals as scripts. The parameters become script bindings. A traversal returns a row per result: a map, from project(), elementMap() or valueMap(), gives a field per key, anything else one field called result. Vertices, edges and paths come back like the nodes, relationships and paths of other graph databases, for example as a graph value with the Return graph option.

The Graph output transform upserts vertices and edges with Gremlin traversals, without scripts. A vertex is identified by its primary properties and gets the first label of a node.

The Check graph database connections action.

The Cypher output and Cypher builder transforms.

The Graph index and Graph constraint actions: create indexes with the schema tools of the server.

The execution logging, the Get graph logging info transform, the Graph logging perspective and the graph database location.

The index checks of the Graph output model validation: Gremlin servers don’t list their indexes. The use of the model is validated.

Neo4j import.

There are no transactions: every request is committed on its own.

The binding names id, label, key and value are reserved by Gremlin servers: don’t use them as parameter names.

Amazon Neptune doesn’t run scripts with bindings: use Graph output to write to Neptune.

Amazon Neptune: the connection only authenticates with a username and password, which Neptune doesn’t use. Requests aren’t signed with AWS Signature Version 4, so IAM database authentication isn’t supported: connect to a Neptune cluster with IAM authentication disabled, over TLS.

Graph output sets vertex properties with single cardinality: an update replaces the value, also on servers which keep a set of values by default, like Neptune.

Graph output needs at least one primary property per node: it looks vertices up by these properties.

Dates and times are stored as UTC dates, the date type every Gremlin server supports.

Create indexes with the schema tools of the server, for example the JanusGraph management API: Graph output looks vertices up by their primary properties.

Gremlin Server has no browser. Tools like Graph Explorer can show its graph through the HTTP endpoint of the server, which needs the WsAndHttpChannelizer in its configuration.