INSERT

Overview

The INSERT statement allows you to add new nodes and edges into the graph using patterns.

In an open graph, you can directly insert nodes and edges, and the corresponding schemas and properties will be automatically created on the fly. When a property is created, its value type is inferred from the first value provided. See the examples below:

On the other hand, in a typed graph, any node or edge inserted must conform to its graph type - nodes or edges with undefined schemas or properties cannot be added.

Preparing a Graph

We will use an open graph to demonstrate node and edge insertion. To create an open graph named myGraph:

CREATE GRAPH myGraph ANY

In a typed graph, the syntax for inserting nodes and edges is the same as in an open graph, but you must ensure that the specified node and edge schemas and properties are already defined in the graph.

Inserting Nodes

Nodes are inserted using node patterns, each of which consists of:

• Variable declaration (Optional): If needs to return the inserted node or reference it in subsequent queries, you can declare a variable for it.
• Label expression (Required): Each node must have exactly one label (i.e., its schema name).
• Property specification (Optional): Assign values to the node’s properties. Note that:
  • If a node _id is not provided, it will be automatically generated by the system; however, you may assign a custom unique value if desired.
  • Node _uuid values are always generated by the system and cannot be manually assigned.
  • For an existing label, any properties not explicitly provided will default to null.

To insert a User and two Club nodes and return them:

INSERT (n1:User {_id: "U01", name: "Quasar92"}), (n2:Club {_id: "C01"}), (n3:Club {since: 2007})
RETURN n1, n2, n3

Result:

+-----+---------------------+--------+----------+
| _id |       _uuid         | Schema |   name   |
+-----+---------------------+--------+----------+
| U01 | 9223375335389659138 |  User  | Quasar92 |
+-----+---------------------+--------+----------+

+-----+---------------------+--------+-------+
| _id |        _uuid        | Schema | since |
+-----+---------------------+--------+-------+
| C01 | 4755803405526499330 |  Club  | null  |
+-----+---------------------+--------+-------+

+--------------------------+----------------------+--------+-------+
|            _id           |         _uuid        | Schema | since |
+--------------------------+----------------------+--------+-------+
| 68ad5fa400000001d4000005 | 11961562809319292931 |  Club  | 2007  |
+--------------------------+----------------------+--------+-------+

To insert anther User node:

INSERT (:User {_id: "U02", name: 'mochaeach', gender: 'female'})

Until now, two node schemas have been created behind the scenes:

• User node schema with two properties: name (STRING type) and gender (STRING type)
• Club node schema with one property: since (INT64 type)

Inserting Edges

Edges are inserted using path patterns where the edge pattern has node patterns on both sides and must include a direction to indicate its source and destination nodes. Each edge pattern consists of:

• Variable declaration (Optional): If needs to return the inserted edge or reference it in subsequent queries, you can declare a variable for it.
• Label expression (Required): Each edge must have exactly one label (i.e., its schema name).
• Property specification (Optional): Assign values to the edge’s properties. Note that:
  • Edge _uuid values are always generated by the system and cannot be manually assigned.
  • Edge _from, _to, _from_uuid, and _to_uuid values are automatically derived from the specified source and destination nodes. They cannot be manually assigned.
  • For an existing label, any properties not explicitly provided will default to null.

When inserting edges, you either connect them to existing nodes in the graph or insert the source and destination nodes along with the edges.

Inserting Nodes Along with Edges

To insert three User nodes and two Follows edges between them:

INSERT (:User {name: 'rowlock'})-[:Follows {createdOn: date('2024-01-05')}]->(:User {name: 'Brainy', gender: 'male'})<-[:Follows {createdOn: date('2024-02-01')}]-(:User {name: 'purplechalk', gender: 'female'})

Connecting to Existing Nodes

To insert and return a Joins edge, with its source and destination nodes being found by the preceding MATCH statement and bound to variables n1 and n2:

MATCH (n1:User {_id: 'U01'}), (n2:Club {_id: 'C01'})
INSERT (n1)-[e:Joins {memberNo: 1}]->(n2)
RETURN e

Result: e

Inserting Connected Paths

To insert two paths that intersect at a node by reusing the variable c02:

INSERT (:User {_id: 'U06', name: 'waveBliss'})-[:Joins {memberNo: 1}]->(c02:Club {_id: 'C02'})<-[:Joins {memberNo: 2}]-(:User {_id: 'U07', name: 'bella', gender: 'female'}), 
       (:User {_id: 'U08', name: 'Roose'})-[:Joins {memberNo: 3}]->(c02)