Neo4j: Best way to batch relate nodes using Cypher?

Question

When I run a script that tries to batch merge all nodes a certain types, I am getting some weird performance results.

When merging 2 collections of nodes (~42k) and (~26

Answer 1

Can you pass the ids in as parameters rather than fetch them from the graph? The query could look like

MATCH (s:ContactPlayer {ContactPrefixTypeId:{cptid})
MERGE (c:ContactPrefixType {ContactPrefixTypeId:{cptid})
MERGE c-[:CONTACT_PLAYER]->s

If you use the REST API Cypher resource, I think the entity should look something like

{
    "query":...,
    "params": {
        "cptid":id1
    }
}

If you use the transactional endpoint, it should look something like this. You control transaction size by the number of statements in each call, and also by the number of calls before you commit. More here.

{
    "statements":[
        "statement":...,
        "parameters": {
            "cptid":id1
        },
        "statement":...,
        "parameters": {
            "cptid":id2
        }
    ]
}