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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] )

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

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.

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

  1. 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"))
    Class('spells')
    Collection("spells")
    Query metrics:

    •    bytesIn:  18

    •   bytesOut:  80

    • computeOps:   1

    •    readOps:   0

    •   writeOps:   0

    •  readBytes:   0

    • writeBytes:   0

    •  queryTime: 4ms

    •    retries:   0

  2. 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")))
    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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