Neo4j Import Tool ID Spaces in Cypher Query

Question

I'm using the Neo4j Import Tool to import some nodes, and am trying to understand how ID spaces and labels work together and affect the behavior of cypher queries that match on nodes with specific IDs.

So for example, suppose I load nodes into two ID spaces ID_SPACE_X and ID_SPACE_Y:

x_nodes.csv:
id:ID(ID_SPACE_X),field1:string,field2:long,:LABEL
1,"foo",42,A

y_nodes.csv:
id:ID(ID_SPACE_Y),field1:string,:LABEL
1,"bar",A

Then I perform the following Cypher query:

MATCH (n:A {id:1}) RETURN n;

Which node is returned? Can you express the ID space in a cypher query in order to return the right node? Or must labels assigned to nodes in one ID space be exclusive to that ID space?

Thanks for any help.

cybersam cybersam · Accepted Answer · 2016-04-29T00:23:31

ID spaces are only meaningful to the Import Tool. They enable the tool to correctly detect uniqueness errors.

They have no connection to node labels.

So, your example is buggy. You are telling the Import Tool that it is OK to create 2 A nodes with the same id property value. This will cause 2 such nodes to be created.

Neo4j Import Tool ID Spaces in Cypher Query

1 Answers