rel = client.relationships.retrieve(external_id="flow1")
rel.confidence = 0.75
res = client.relationships.update(rel)

from cognite.client.data_classes import RelationshipUpdate
my_update = RelationshipUpdate(external_id="flow_1").source_external_id.set("alternate_source").confidence.set(0.97)
res1 = client.relationships.update(my_update)
another_update = RelationshipUpdate(external_id="flow_1").confidence.set(None)
res2 = client.relationships.update(another_update)

from cognite.client.data_classes import RelationshipUpdate
my_update = RelationshipUpdate(external_id="flow_1").labels.add(["PUMP", "VERIFIED"])
res = client.relationships.update(my_update)

from cognite.client.data_classes import RelationshipUpdate
my_update = RelationshipUpdate(external_id="flow_1").labels.remove("PUMP")
res = client.relationships.update(my_update)

List<Relationship> relationshipList = // list of Relationship for update; 
List<Relationship> upsertRelationshipsList = 
          client.relationships().upsert(relationshipList);

curl --request POST \
  --url https://{cluster}.cognitedata.com/api/v1/projects/{project}/relationships/update \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "items": [
    {
      "externalId": "<string>",
      "update": {
        "confidence": {
          "set": 0.5
        },
        "startTime": {
          "set": 1730204346000
        },
        "endTime": {
          "set": 1730204346000
        },
        "dataSetId": {
          "set": 4503599627370496
        },
        "labels": {
          "add": [
            {
              "externalId": "my.known.id"
            }
          ],
          "remove": [
            {
              "externalId": "my.known.id"
            }
          ]
        }
      }
    }
  ]
}
'

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    items: [
      {
        externalId: '<string>',
        update: {
          confidence: {set: 0.5},
          startTime: {set: 1730204346000},
          endTime: {set: 1730204346000},
          dataSetId: {set: 4503599627370496},
          labels: {add: [{externalId: 'my.known.id'}], remove: [{externalId: 'my.known.id'}]}
        }
      }
    ]
  })
};

fetch('https://{cluster}.cognitedata.com/api/v1/projects/{project}/relationships/update', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://{cluster}.cognitedata.com/api/v1/projects/{project}/relationships/update",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'items' => [
        [
                'externalId' => '<string>',
                'update' => [
                                'confidence' => [
                                                                'set' => 0.5
                                ],
                                'startTime' => [
                                                                'set' => 1730204346000
                                ],
                                'endTime' => [
                                                                'set' => 1730204346000
                                ],
                                'dataSetId' => [
                                                                'set' => 4503599627370496
                                ],
                                'labels' => [
                                                                'add' => [
                                                                                                                                [
                                                                                                                                                                                                                                                                'externalId' => 'my.known.id'
                                                                                                                                ]
                                                                ],
                                                                'remove' => [
                                                                                                                                [
                                                                                                                                                                                                                                                                'externalId' => 'my.known.id'
                                                                                                                                ]
                                                                ]
                                ]
                ]
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://{cluster}.cognitedata.com/api/v1/projects/{project}/relationships/update"

	payload := strings.NewReader("{\n  \"items\": [\n    {\n      \"externalId\": \"<string>\",\n      \"update\": {\n        \"confidence\": {\n          \"set\": 0.5\n        },\n        \"startTime\": {\n          \"set\": 1730204346000\n        },\n        \"endTime\": {\n          \"set\": 1730204346000\n        },\n        \"dataSetId\": {\n          \"set\": 4503599627370496\n        },\n        \"labels\": {\n          \"add\": [\n            {\n              \"externalId\": \"my.known.id\"\n            }\n          ],\n          \"remove\": [\n            {\n              \"externalId\": \"my.known.id\"\n            }\n          ]\n        }\n      }\n    }\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://{cluster}.cognitedata.com/api/v1/projects/{project}/relationships/update")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"items\": [\n    {\n      \"externalId\": \"<string>\",\n      \"update\": {\n        \"confidence\": {\n          \"set\": 0.5\n        },\n        \"startTime\": {\n          \"set\": 1730204346000\n        },\n        \"endTime\": {\n          \"set\": 1730204346000\n        },\n        \"dataSetId\": {\n          \"set\": 4503599627370496\n        },\n        \"labels\": {\n          \"add\": [\n            {\n              \"externalId\": \"my.known.id\"\n            }\n          ],\n          \"remove\": [\n            {\n              \"externalId\": \"my.known.id\"\n            }\n          ]\n        }\n      }\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "items": [
    {
      "externalId": "<string>",
      "sourceExternalId": "<string>",
      "targetExternalId": "<string>",
      "createdTime": 1730204346000,
      "lastUpdatedTime": 1730204346000,
      "startTime": 1730204346000,
      "endTime": 1730204346000,
      "confidence": 0.5,
      "dataSetId": 4503599627370496,
      "labels": [
        {
          "externalId": "my.known.id"
        }
      ]
    }
  ]
}

{
  "error": {
    "code": 409,
    "message": "Could not authenticate.",
    "missing": [
      {}
    ],
    "duplicated": [
      {}
    ]
  }
}

{
  "error": {
    "code": 409,
    "message": "Could not authenticate.",
    "missing": [
      {}
    ],
    "duplicated": [
      {}
    ]
  }
}