apoc.refactor.mergeNodes

Details
Syntax	`apoc.refactor.mergeNodes(nodes [, config ]) :: (node)`
Description	Merges the given `LIST<NODE>` onto the first `NODE` in the `LIST<NODE>`. All `RELATIONSHIP` values are merged onto that `NODE` as well.
Input arguments	Name	Type	Description
	`nodes`	`LIST<NODE>`	The nodes to be merged onto the first node.
	`config`	`MAP`	`{ mergeRels :: BOOLEAN, selfRef :: BOOLEAN, produceSelfRef = true :: BOOLEAN, preserveExistingSelfRels = true :: BOOLEAN, countMerge = true :: BOOLEAN, collapsedLabel :: BOOLEAN, singleElementAsArray = false :: BOOLEAN, avoidDuplicates = false :: BOOLEAN, relationshipSelectionStrategy = "incoming" :: ["incoming", "outgoing", "merge"] properties :: ["overwrite", ""discard", "combine"] }`. The default is: `{}`.
Return arguments	Name	Type	Description
Return arguments	`node`	`NODE`	The merged node.

Usage Examples

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

CREATE (n1:Person {name:'Tom'}),
(n2:Person {name:'John'}),
(n3:Company {name:'Company1'}),
(n5:Car {brand:'Ferrari'}),
(n6:Animal:Cat {name:'Derby'}),
(n7:City {name:'London'}),

(n1)-[:WORKS_FOR {since:2015}]->(n3),
(n2)-[:WORKS_FOR {since:2018}]->(n3),
(n3)-[:HAS_HQ {since:2004}]->(n7),
(n1)-[:DRIVE {since:2017}]->(n5),
(n2)-[:HAS {since:2013}]->(n6);

The following merges John and Tom into a single node:

MATCH (a1:Person{name:'John'}), (a2:Person {name:'Tom'})
WITH head(collect([a1,a2])) as nodes
CALL apoc.refactor.mergeNodes(nodes,{
  properties:"combine",
  mergeRels:true
})
YIELD node
RETURN node;

Results
node
(:Person {name: ["John", "Tom"]})

More documentation of apoc.refactor.mergeNodes