firebase-database/io.github.corneloaie.firebase.database/DatabaseReference

DatabaseReference

A Firebase reference represents a particular location in your Database and can be used for reading or writing data to that Database location.

This class is the starting point for all Database operations. After you've initialized it with a URL, you can use it to read data, write data, and to create new DatabaseReferences.

Properties

android

val DatabaseReference.android: DatabaseReference

val Query.android: Query

The underlying Firebase Android SDK object.

compat

open override val compat: DatabaseReference

The Android-SDK-shaped com.google.firebase.database.DatabaseReference this wraps.

database

val Query.database: Database

The underlying Firebase JS SDK database.

val Query.database: Database

The underlying Firebase JS SDK database.

ios

val DatabaseReference.ios: FIRDatabaseReference

val Query.ios: FIRDatabaseQuery

The underlying Firebase iOS SDK object.

val Query.js: Query

The underlying Firebase JS SDK object.

val Query.js: Query

The underlying Firebase JS SDK object.

key

val key: String?

persistenceEnabled

val Query.~~persistenceEnabled~~: Boolean

valueEvents

val valueEvents: Flow<DataSnapshot>

The data at this location and every change to it; the flow fails if the listener is cancelled.

Functions

child

fun child(path: String): DatabaseReference

Get a reference to location relative to this one

childEvents

fun childEvents(vararg types: ChildEvent.Type = arrayOf(ADDED, CHANGED, MOVED, REMOVED)): Flow<ChildEvent>

The changes to the children of this location of the given types; the flow fails if the listener is cancelled.

endAt

fun endAt(value: Boolean, key: String? = null): Query

fun endAt(value: Double, key: String? = null): Query

fun endAt(value: String, key: String? = null): Query

Creates a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default.

equals

open operator override fun equals(other: Any?): Boolean

equalTo

fun equalTo(value: Boolean, key: String? = null): Query

fun equalTo(value: Double, key: String? = null): Query

fun equalTo(value: String, key: String? = null): Query

Creates a query constrained to only return child nodes with the given value.

get

suspend fun get(): DataSnapshot

Gets the server values for this query. Updates the cache and raises events if successful. If not connected, falls back to a locally-cached value or null.

hashCode

open override fun hashCode(): Int

limitToFirst

fun limitToFirst(limit: Int): Query

Creates a query with limit and anchor it to the start of the window.

limitToLast

fun limitToLast(limit: Int): Query

Creates a query with limit and anchor it to the end of the window.

onDisconnect

fun onDisconnect(): OnDisconnect

Provides access to disconnect operations at this location

orderByChild

fun orderByChild(path: String): Query

Creates a query in which child nodes are ordered by the values of the specified path.

orderByKey

fun orderByKey(): Query

Creates a query in which child nodes are ordered by their keys.

orderByValue

fun orderByValue(): Query

Creates a query in which nodes are ordered by their value

push

fun push(): DatabaseReference

Create a reference to an auto-generated child location. The child key is generated client-side and incorporates an estimate of the server's time for sorting purposes. Locations generated on a single client will be sorted in the order that they are created, and will be sorted approximately in order across all clients.

removeValue

suspend fun removeValue()

Set the value at this location to 'null'

runTransaction

suspend fun <T> runTransaction(strategy: KSerializer<T>, buildSettings: EncodeDecodeSettingsBuilder.() -> Unit = {}, transactionUpdate: (currentData: T) -> T): DataSnapshot

Run a transaction on the data at this location.

setValue

inline suspend fun <T> ~~setValue~~(value: T?, encodeDefaults: Boolean)

suspend fun <T> ~~setValue~~(strategy: SerializationStrategy<T>, value: T, encodeDefaults: Boolean)

inline suspend fun <T> setValue(strategy: SerializationStrategy<T>, value: T, buildSettings: EncodeSettings.Builder.() -> Unit = {})

inline suspend fun <T> setValue(value: T?, buildSettings: EncodeSettings.Builder.() -> Unit = {})

Sets the value at this location, suspending until the server has acknowledged the write.

startAt

fun startAt(value: Boolean, key: String? = null): Query

fun startAt(value: Double, key: String? = null): Query

fun startAt(value: String, key: String? = null): Query

Creates a query constrained to only return child nodes with a value greater than or equal to the given value, using the given orderBy directive or priority as default.

toString

open override fun toString(): String

updateChildren

suspend fun ~~updateChildren~~(update: Map<String, Any?>, encodeDefaults: Boolean)

inline suspend fun updateChildren(update: Map<String, Any?>, buildSettings: EncodeSettings.Builder.() -> Unit = {})

Update the specific child keys to the specified values. Passing null in a map to updateChildren() will remove the value at the specified location.