apoc.create.setRelProperty

Procedure APOC Core

apoc.create.setRelProperty( [rel,id,ids,rels], key, value) - sets the given property on the relationship(s)

Signature

apoc.create.setRelProperty(relationships :: ANY?, key :: STRING?, value :: ANY?) :: (rel :: RELATIONSHIP?)

Input parameters

Name	Type	Default
relationships	ANY?	null
key	STRING?	null
value	ANY?	null

Name

Type

Default

relationships

ANY?

null

key

STRING?

null

value

ANY?

null

Output parameters

Name	Type
rel	RELATIONSHIP?

Usage Examples

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

CREATE (station1:Station {name: "Station 1"})
CREATE (station2:Station {name: "Station 3"})
CREATE (station1)-[:JOURNEY {arrival: "0802", departure: "0803"}]->(station2);

We want to convert the arrival and departure properties into Time types and store them as new properties, whose names are based on the original property keys.

We can generate the new property keys and Time values, by running the following query:

MATCH (:Station)-[journey:JOURNEY]->(:Station)
UNWIND ["arrival", "departure"] AS key
RETURN key + "Time" AS newKey, time(journey[key]) AS time;

Table 1. Results
newKey
time
"arrivalTime"
08:02Z
"departureTime"
08:03Z

But if we try to save these properties back to the database:

MATCH (:Station)-[journey:JOURNEY]->(:Station)
UNWIND ["arrival", "departure"] AS key
WITH stop, key + "Time" AS newKey, time(journey[key]) AS time
SET journey[newKey] = time;

We’ll receive the following error:

Results

Invalid input '[': expected ":" (line 5, column 12 (offset: 160))
"SET journey[newKey] = time;"
            ^

We can use apoc.create.setRelProperty to work around this problem, as shown in the query below:

MATCH (:Station)-[journey:JOURNEY]->(:Station)
UNWIND ["arrival", "departure"] AS key
WITH journey, key + "Time" AS newKey, time(journey[key]) AS time
CALL apoc.create.setRelProperty(journey, newKey, time)
YIELD rel
RETURN rel;

Table 2. Results
rel
[:JOURNEY {departure: "0803", arrival: "0802", arrivalTime: 08:02Z}]
[:JOURNEY {departureTime: 08:03Z, departure: "0803", arrival: "0802", arrivalTime: 08:02Z}]

More documentation of apoc.create.setRelProperty