SET

Overview

The SET statement allows you to set properties and labels on nodes and edges. These nodes or edges must first be retrieved using the MATCH statement.

Note:

• In typed graphs, the schema of a node or edge is immutable.
• The values _id, _uuid, _from, _to, _from_uuid, and _to_uuid are immutable.

Typed Graph

Example Graph

CREATE GRAPH myGraph {
  NODE User ({name STRING, gender STRING}),
  NODE Club (),
  EDGE Follows ()-[{createdOn DATE}]->(),
  EDGE Joins ()-[{memberNo INT32}]->()
}

INSERT (rowlock:User {_id: "U01", name: "rowlock"}),
       (brainy:User {_id: "U02", name: "Brainy", gender: "male"}),
       (purplechalk:User {_id: "U03", name: "purplechalk", gender: "female"}),
       (mochaeach:User {_id: "U04", name: "mochaeach", gender: "female"}),
       (c:Club {_id: "C01"}),
       (rowlock)-[:Follows {createdOn: date("2024-01-05")}]->(brainy),
       (purplechalk)-[:Follows {createdOn: date("2024-02-01")}]->(brainy),
       (mochaeach)-[:Follows {createdOn: date("2024-02-10")}]->(brainy),
       (brainy)-[:Joins {memberNo: 1}]->(c)

Updating Property Values

To update the values of specified properties:

MATCH (n:User {name: 'rowlock'})-[e:Follows]->(:User {name: 'Brainy'})
SET n.gender = 'male', e.createdOn = '2024-01-07'
RETURN n.gender, e.createdOn

Removing Property Values

To remove the values of specified properties by setting them to null:

MATCH (n:User {name: 'mochaeach'})
SET n.gender = null
RETURN n

Overwriting All Property Values

To overwrite all property values, the mentioned property values will be updated while others will be set to null:

MATCH (n:User {name: 'purplechalk'})
SET n = {name: 'MasterSwift'}
RETURN n

Removing All Property Values

To remove all property values by setting an empty specification:

MATCH (n:User {name: 'rowlock'})
SET n = {}
RETURN n

Mismatched Value Type

If the provided value does not match the property's expected value type and cannot be converted, the property will be assigned its default value based on the property value type.

To update memberNo (UINT64 type) of the retrieved edge with a string:

MATCH ()-[e:Joins]->()
SET e.memberNo = 'm2'
RETURN e

Result: e

Open Graph

Example Graph

CREATE GRAPH myGraph ANY

INSERT (rowlock:User {_id: "U01", name: "rowlock"}),
       (brainy:User {_id: "U02", name: "Brainy", gender: "male"}),
       (purplechalk:User {_id: "U03", name: "purplechalk", gender: "female"}),
       (mochaeach:User {_id: "U04", name: "mochaeach", gender: "female"}),
       (c:Club {_id: "C01"}),
       (rowlock)-[:Follows {createdOn: date("2024-01-05")}]->(brainy),
       (purplechalk)-[:Follows {createdOn: date("2024-02-01")}]->(brainy),
       (mochaeach)-[:Follows {createdOn: date("2024-02-10")}]->(brainy),
       (brainy)-[:Joins {memberNo: 1}]->(c)

Adding Labels

To add a label to a node:

MATCH (n:User {name: 'rowlock'})
SET n:Person

To add two labels to a node:

MATCH (n:User {name: 'rowlock'})
SET n:Player, n:Employee

Updating Property Values

To update the values of specified properties:

MATCH (n:User {name: 'rowlock'})-[e:Follows]->(:User {name: 'Brainy'})
SET n.gender = 'male', e.createdOn = '2024-01-07'
RETURN n.gender, e.createdOn

Overwriting All Property Values

To overwrite all property values:

MATCH (n:User {name: 'purplechalk'})
SET n = {name: 'MasterSwift'}
RETURN n