apoc.refactor.categorize

Details
Syntax	`apoc.refactor.categorize(sourceKey, type, outgoing, label, targetKey, copiedKeys, batchSize)`
Description	Creates new category `NODE` values from `NODE` values in the graph with the specified `sourceKey` as one of its property keys. The new category `NODE` values are then connected to the original `NODE` values with a `RELATIONSHIP` of the given type.
Input arguments	Name	Type	Description
	`sourceKey`	`STRING`	The property key to add to the on the new node.
	`type`	`STRING`	The relationship type to connect to the new node.
	`outgoing`	`BOOLEAN`	Whether the relationship should be outgoing or not.
	`label`	`STRING`	The label of the new node.
	`targetKey`	`STRING`	The name by which the source key value will be referenced on the new node.
	`copiedKeys`	`LIST<STRING>`	A list of additional property keys to be copied to the new node.
	`batchSize`	`INTEGER`	The max size of each batch.

Usage Examples

The examples in this section are based on the following sample graph:

CREATE (:Movie {title: 'A Few Good Men', genre: 'Drama'});

We want to move the genre from the Movie node to a new node with the Genre label and name property. We’ll also create a GENRE relationship from the Movie node to that genre node.

This procedure requires us to create a unique constraint on the Genre label, name property, otherwise we’ll get the following exception:

CALL apoc.refactor.categorize('genre', 'GENRE', true, "Genre", "name", [], 100);

Results

Failed to invoke procedure `apoc.refactor.categorize`: Caused by: java.lang.IllegalArgumentException: Before execute this procedure you must define an unique constraint for the label and the targetKey:
CREATE CONSTRAINT FOR (n:`Genre`) REQUIRE n.`name` IS UNIQUE

Once we’ve created the constraint, we can re-run the procedure, and then see the new graph structure by running the following query:

MATCH p=()-[:GENRE]->()
RETURN p;

Figure 1. New graph structure