Database
class Database : NSObject
The entry point for accessing a Firebase Database. You can get an instance
by calling Database.database()
. To access a location in the database and
read or write data, use FIRDatabase.reference()
.
-
Unavailable
use the database method instead
The NSObject initializer that has been marked as unavailable. Use the
database
class method instead. -
Gets the instance of
Database
for the defaultFirebaseApp
.Declaration
Swift
class func database() -> Database
Return Value
A
Database
instance. -
Gets a
Database
instance for the specified URL.Declaration
Swift
class func database(url: String) -> Database
Parameters
url
The URL to the Firebase Database instance you want to access.
Return Value
A
Database
instance. -
Gets a
Database
instance for the specified URL, using the specifiedFirebaseApp
.Declaration
Swift
class func database(app: FIRApp, url: String) -> Database
Parameters
app
The app to get a
Database
for.url
The URL to the Firebase Database instance you want to access.
Return Value
A
Database
instance. -
Gets an instance of
Database
for a specificFirebaseApp
.Declaration
Swift
class func database(app: FIRApp) -> Database
Parameters
app
The app to get a
Database
for.Return Value
A
Database
instance. -
The app instance to which this
Database
belongs.Declaration
Swift
weak var app: FIRApp? { get }
-
Gets a
DatabaseReference
for the root of your Firebase Database.Declaration
Swift
func reference() -> DatabaseReference
-
Gets a
DatabaseReference
for the provided path.Declaration
Swift
func reference(withPath path: String) -> DatabaseReference
Parameters
path
Path to a location in your Firebase Database.
Return Value
A
DatabaseReference
pointing to the specified path. -
Gets a
DatabaseReference
for the provided URL. The URL must be a URL to a path within this Firebase Database. To create aDatabaseReference
to a different database, create aFirebaseApp
with anOptions
object configured with the appropriate database URL.Declaration
Swift
func reference(fromURL databaseUrl: String) -> DatabaseReference
Parameters
databaseUrl
A URL to a path within your database.
Return Value
A
DatabaseReference
for the provided URL. -
The Firebase Database client automatically queues writes and sends them to the server at the earliest opportunity, depending on network connectivity. In some cases (e.g. offline usage) there may be a large number of writes waiting to be sent. Calling this method will purge all outstanding writes so they are abandoned.
All writes will be purged, including transactions and onDisconnect writes. The writes will be rolled back locally, perhaps triggering events for affected event listeners, and the client will not (re-)send them to the Firebase Database backend.
Declaration
Swift
func purgeOutstandingWrites()
-
Shuts down the connection to the Firebase Database backend until
goOnline()
is called.Declaration
Swift
func goOffline()
-
Resumes the connection to the Firebase Database backend after a previous goOffline() call.
Declaration
Swift
func goOnline()
-
The Firebase Database client will cache synchronized data and keep track of all writes you’ve initiated while your application is running. It seamlessly handles intermittent network connections and re-sends write operations when the network connection is restored.
However by default your write operations and cached data are only stored in-memory and will be lost when your app restarts. By setting this value to
true
, the data will be persisted to on-device (disk) storage and will thus be available again when the app is restarted (even when there is no network connectivity at that time). Note that this property must be set before creating your firstDatabaseReference
and only needs to be called once per application.Declaration
Swift
var isPersistenceEnabled: Bool { get set }
-
By default the Firebase Database client will use up to 10MB of disk space to cache data. If the cache grows beyond this size, the client will start removing data that hasn’t been recently used. If you find that your application caches too little or too much data, call this method to change the cache size. This property must be set before creating your first
DatabaseReference
and only needs to be called once per application.Note that the specified cache size is only an approximation and the size on disk may temporarily exceed it at times. Cache sizes smaller than 1 MB or greater than 100 MB are not supported.
Declaration
Swift
var persistenceCacheSizeBytes: UInt { get set }
-
Sets the dispatch queue on which all events are raised. The default queue is the main queue.
Note that this must be set before creating your first Database reference.
Declaration
Swift
var callbackQueue: dispatch_queue_t { get set }
-
Enables verbose diagnostic logging.
Declaration
Swift
class func setLoggingEnabled(_ enabled: Bool)
Parameters
enabled
true to enable logging, false to disable.
-
Retrieve the Firebase Database SDK version.
Declaration
Swift
class func sdkVersion() -> String
-
Configures the database to use an emulated backend instead of the default remote backend.
Declaration
Swift
func useEmulator(withHost host: String, port: Int)
-
Undocumented
Declaration
Swift
typealias Encoder = FirebaseDataEncoder
-
Undocumented
Declaration
Swift
typealias Decoder = FirebaseDataDecoder