FQL v4 will be decommissioned on June 30, 2025. Ensure that you complete your migration from FQL v4 to FQL v10 by that date.

Fauna accounts created after August 21, 2024 must use FQL v10. These accounts will not be able to run FQL v4 queries or access the v4 Dashboard.

For more details, see the v4 EOL announcement and migration guide. Contact support@fauna.com with any questions.

Update

This reference topic applies to FQL v4. Go to this page for the latest FQL v10 reference topics.

 
Update( ref, param_object )
q.update( ref param_object )
Update( ref, param_object )
Update( ref, param_object )
Update( ref, param_object )
Update( ref, param_object )

Description

The Update operation only modifies the specified fields in the documents pointed to by ref. Updates are partial, and only modify values that are specified in the param_object. Changes to scalar values and arrays are entirely replaced by the new data. Modifications to objects are merged. Setting a value to null completely removes the value. Fields in the document not specified in the param_object are not modified.

For performance, the documents describing AccessProviders, Databases, Collections, Functions, Indexes, Keys, Roles, and Tokens use an object cache. When you use Update to modify any of these Fauna schema documents, the modification is not guaranteed to be visible immediately.

This does not apply to non-schema documents, such as those in a user-created collection. Non-schema documents are always modified or removed in a strongly consistent manner.

Parameters

Parameter Type Definition and Requirements

ref

Reference

A Reference identifying the document that should be modified.

param_object

Object

An Object containing the document data to update, as well as optional new credentials and delegates. See the following section for details.

param_object

Field Name Field Type Definition and Requirements

data

Object

The document’s user data to be modified.

credentials

Object

The document’s credentials to be modified.

delegates

Object

The document’s delegates to be modified.

ttl

Timestamp

Optional - A timestamp that indicates the time-to-live for a document, which is when the document is removed from the collection and can’t be queried. The document history can continue to be accessed using the Events function, provided the events are in the history retention interval and the document reference is input to the Events function.

Returns

An object containing the metadata about the update operations.

Field Name Field Type Definition and Requirements

ref

Reference

The Reference that identifies the document that was updated.

data

Object

A copy of the new document data.

ts

Long

The timestamp, with microsecond resolution, of the document update.

Examples

The following query updates the document by changing the name field to the value "Mountains’s Thunder" and removing the cost field from the document. All other fields in the document remain unchanged.

client.query(
  q.Update(
    q.Ref(q.Collection('spells'), '181388642581742080'),
    {
      data: {
        name: 'Mountain\'s Thunder',
        cost: null,
      },
    },
  )
)
.then((ret) => console.log(ret))
.catch((err) => console.error(
  'Error: [%s] %s: %s',
  err.name,
  err.message,
  err.errors()[0].description,
))
{
  ref: Ref(Collection("spells"), "181388642581742080"),
  ts: 1592112267090000,
  data: { name: "Mountain's Thunder", element: 'air' }
}
result = client.query(
  q.update(
    q.ref(q.collection("spells"), "181388642581742080"),
    {
      "data": {
        "name": "Mountain's Thunder",
        "cost": None
      }
    }
  )
)
print(result)
{'ref': Ref(id=181388642581742080, collection=Ref(id=spells, collection=Ref(id=collections))), 'ts': 1592870397530000, 'data': {'name': "Mountain's Thunder", 'element': 'air'}}
result, err := client.Query(
	f.Update(
		f.Ref(f.Collection("spells"), "181388642581742080"),
		f.Obj{
			"data": f.Obj{"name": "Mountain's Thunder", "cost": nil}}))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}
map[data:map[element:air name:Mountain's Thunder] ref:{181388642581742080 0xc000146180 0xc000146180 <nil>} ts:1603747313810000]
try
{
    Value result = await client.Query(
        Update(
            Ref(Collection("spells"), "181388642581742080"),
            Obj("data", Obj("name", "Mountain's Thunder", "cost", Null()))
        )
    );
    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}
ObjectV(ref: RefV(id = "181388642581742080", collection = RefV(id = "spells", collection = RefV(id = "collections"))),ts: LongV(1603756871700000),data: ObjectV(name: StringV(Mountain's Thunder),element: StringV(air)))
System.out.println(
    client.query(
        Update(
            Ref(Collection("spells"), Value("181388642581742080")),
            Obj(
                "data", Obj(
                    "name", Value("Mountain's Thunder"),
                    "cost", Null()
                )
            )
        )
    ).get());
{ref: ref(id = "181388642581742080", collection = ref(id = "spells", collection = ref(id = "collections"))), ts: 1593467851740000, data: {name: "Mountain's Thunder", element: "air"}}
Update(
  Ref(Collection('spells'), '181388642581742080'),
  {
    data: {
      name: 'Mountain\'s Thunder',
      cost: null,
    },
  },
)
{
  ref: Ref(Collection("spells"), "181388642581742080"),
  ts: 1624310557810000,
  data: { name: "Mountain's Thunder", element: 'air' }
}
Query metrics:

  •    bytesIn:  150

  •   bytesOut:  213

  • computeOps:    1

  •    readOps:    0

  •   writeOps:    1

  •  readBytes:   99

  • writeBytes:  117

  •  queryTime: 46ms

  •    retries:    0

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