apoc.nodes.link

Details
Syntax	`apoc.nodes.link(nodes, type [, config ])`
Description	Creates a linked list of the given `NODE` values connected by the given `RELATIONSHIP` type.
Input arguments	Name	Type	Description
	`nodes`	`LIST<NODE>`	The list of nodes to be linked.
	`type`	`STRING`	The relationship type name to link the nodes with.
	`config`	`MAP`	`{ avoidDuplicates = false :: BOOLEAN }` The default is: `{}`.

Config parameters

This procedure supports the following config parameters:

Config parameters
Name	Type	Default	Description
`avoidDuplicates`	`BOOLEAN`	false	If true, the relationship will not be created, if it already exists

Usage Examples

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

CREATE (:Event {name: "Event 1", date: datetime("2019-06-01")})
CREATE (:Event {name: "Event 2", date: datetime("2019-06-04")})
CREATE (:Event {name: "Event 3", date: datetime("2019-06-08")});

We can create a linked list of these events, by running the following query:

MATCH (e:Event)
WITH e ORDER BY e.date
WITH collect(e) AS events
CALL apoc.nodes.link(events, "NEXT")
RETURN count(*);

We can check for relationship existence using the {avoidDuplicates: true} configuration; calling the previous query twice, 2 relations of type "NEXT" will be created between the nodes, instead, by executing CALL apoc.nodes.link(events, "NEXT", {avoidDuplicates: true}) only one relationship of type "NEXT" will be created.