apoc.merge.relationship.eager
Procedure

Details
Syntax	`apoc.merge.relationship.eager(startNode, relType, identProps, onCreateProps, endNode [, onMatchProps ]) :: (rel)`
Description	Merges the given `RELATIONSHIP` values with the given dynamic types/properties eagerly.
Input arguments	Name	Type	Description
	`startNode`	`NODE`	The start node of the relationship.
	`relType`	`STRING`	The type of the relationship.
	`identProps`	`MAP`	Properties on the relationship that are always merged.
	`onCreateProps`	`MAP`	Properties that are merged when a relationship is created.
	`endNode`	`NODE`	The end node of the relationship.
	`onMatchProps`	`MAP`	Properties that are merged when a relationship is matched. The default is: `{}`.
Return arguments	Name	Type	Description
Return arguments	`rel`	`RELATIONSHIP`	The updated relationship.

Example

Given this dataset:

CREATE (:Person {name: 'Alice'}), (:Person {name: 'Bob'})

The following query merges a KNOWS relationship between two existing nodes, using id as the identifying property and since as an on-create property:

MATCH (a:Person {name: 'Alice'}), (b:Person {name: 'Bob'})
CALL
  apoc.merge.relationship.eager(
    a,
    'KNOWS',
    {id: 1},
    {since: 2019},
    b,
    {}
  )
  YIELD rel
RETURN type(rel) AS type, rel.id AS id, rel.since AS since

Results
type	id	since
"KNOWS"	1	2019

Produces the same result as apoc.merge.relationship. The eager variant fully materializes all results before returning, which prevents conflicts when the procedure is used inside a larger query that also reads or writes relationships of the same type. Calling the procedure again with the same identProps returns the existing relationship without creating a duplicate; any onMatchProps are applied to the matched relationship instead.

More documentation of apoc.merge.relationship.eager

apoc.merge.relationship.eagerProcedure

Example

apoc.merge.relationship.eager
Procedure