Neo4j
Description
Neo4j is an open source graph database which you can download from www.neo4j.com/download-center
You can use it to represent information with nodes and relationships in a property graph. Neo4j doesn’t use indexes which allows it to traverse large graphs really quickly with so-called graph algorithms. For more information on these unique graph algorithms see: Neo4j Graph Algorithms
Hop supports Neo4j through the following metadata objects
Perspective: Execution lineage
You can use Neo4j to store logging and execution lineage of your workflows and pipelines. The way you do this is simply by setting the variable NEO4J_LOGGING_CONNECTION
to the name of the Neo4j Connection where you want the logging and lineage to be written to.
The Neo4j plugin offers a separate perspective to query this logging and lineage information. For example, it allows you to quickly jump to the place where an error occurred. This neat trick is performed by asking the database to find the shortest path between and execution node where an error occurred and without children and the “grand parent” node. The path you get is the exact path that was followed from for example the “grand parent” workflow to the exact transform where an error occurred.
Metadata Types
Neo4j Connection: create or manage a connection to a Neo4j database
Neo4j Graph Model: crearte or manage a Neo4j (sub)graph model
Workflow Actions
Neo4j Check Connection: check a connection to a Neo4j database
Neo4j Cypher Script: execute a Cypher script or query
Neo4j Index: Create or drop Neo4j indexes
Neo4j Constraint: Create or drop Neo4j constraints
Pipeline Transforms
Neo4j Cypher: execute a Cypher query on a Neo4j database using parameter info from input fields
Neo4j Generate CSVs: Generate CSV files for nodes and relationships to be used with neo4j-import
Neo4j Get Log Info: Queries the Neo4j logging graph for execution info
Neo4j Graph Output: Writes to a Neo4j graph using an input fields mapping.
Neo4j Import: Runs a Neo4j import command using the provided CSV files
Neo4j Output: Write nodes and/or relationships to a Neo4j graph
Neo4j Split Graph: Splits the nodes and relationships of a Neo4j graph