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.

`Class`

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

Class( name, [database] )

class_( name, [database] )

Class( name )
ScopedClass( name, database )

Class( name, [database] )

Class( name, [database] )

Class( name, [database] )

Description

This function is deprecated as of Fauna 2.7.0. Use Collection instead.

A Class was renamed to a Collection in Fauna 2.7.0. This function continues to exist for compatibility with older drivers.

The Class function returns a valid Reference for the specified class (now, collection) name, in the specified child database. If a child database is not specified, the returned class (now, collection) reference belongs to the current database.

When a child database is specified, an admin key must be used to call Class (server or client keys, or ABAC tokens, cannot be used to access a child database).

Also, Go does not support optional function parameters, nor function overloading. To specify a child database using the Go driver, call the ScopedClass function instead of Class.

Parameters

Parameter Type Definition and Requirements

Parameter	Type	Definition and Requirements
`name`	String	The name of a class (now, collection).
`database`	Reference	Optional - A Reference to a child database. If not specified, the current database is used. A Reference to a child database. Optional - A Reference to a child database. If not specified, the current database is used. Optional - A Reference to a child database. If not specified, the current database is used. Optional - A Reference to a child database. If not specified, the current database is used. Optional - A Reference to a child database. If not specified, the current database is used. Optional - A Reference to a child database. If not specified, the current database is used.

name

String

The name of a class (now, collection).

database

Reference

Optional - A Reference to a child database. If not specified, the current database is used.

A Reference to a child database.

Optional - A Reference to a child database. If not specified, the current database is used.

Returns

A Reference to a class (now, collection) with the specified name, in the specified child database (or the current database if database is not specified).

Examples

The following query gets a Reference to the class (now, collection) named "spells" within the current database:

client.query(
  q.Class('spells')
)
.then((ret) => console.log(ret))
.catch((err) => console.error(
  'Error: [%s] %s: %s',
  err.name,
  err.message,
  err.errors()[0].description,
))

Collection("spells")

result = client.query(
    q.class_("spells")
)
print(result)

Ref(id=spells, collection=Ref(id=collections))

result, err := client.Query(
	f.Class("spells"))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}

{spells 0xc000090360 0xc000090360 <nil>}

try
{
    Value result = await client.Query(
        Class("spells")
    );
    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}

RefV(id = "spells", collection = RefV(id = "collections"))

System.out.println(
    client.query(
        Class("spells")
    ).get());

ref(id = "spells", collection = ref(id = "collections"))

Class('spells')

Collection("spells")

Query metrics:

bytesIn: 18
bytesOut: 80
computeOps: 1
readOps: 0
writeOps: 0
readBytes: 0
writeBytes: 0
queryTime: 4ms
retries: 0

The following query gets a Reference to the class (now, collection) named "spells" within a child database named "child_db":

client.query(
  q.Class('spells', q.Database('child_db'))
)
.then((ret) => console.log(ret))
.catch((err) => console.error(
  'Error: [%s] %s: %s',
  err.name,
  err.message,
  err.errors()[0].description,
))

Collection("spells", Database("child_db"))

result = client.query(
    q.class_("spells", q.database("child_db"))
)
print(result)

Ref(id=spells, collection=Ref(id=collections), database=Ref(id=child_db, collection=Ref(id=databases)))

result, err := client.Query(
	f.ScopedClass("spells", f.Database("child_db")))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}

{spells 0xc0000902d0 0xc0000902d0 0xc000090330}

try
{
    Value result = await client.Query(
        Class("spells", Database("child_db"))
    );
    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}

RefV(id = "spells", collection = RefV(id = "collections"), database = RefV(id = "child_db", collection = RefV(id = "databases")))

System.out.println(
    client.query(
        Class("spells", Database("child_db"))
    ).get());

ref(id = "spells", collection = ref(id = "collections"), database = ref(id = "child_db", collection = ref(id = "databases")))

Class('spells', Database('child_db'))

Collection("spells", Database("child_db"))

Query metrics:

bytesIn: 50
bytesOut: 159
computeOps: 1
readOps: 0
writeOps: 0
readBytes: 155
writeBytes: 0
queryTime: 7ms
retries: 0

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