Error code returned by Firebase RealtimeDatabase C++ functions.

Specifies whether the transaction succeeded or not.

Your own transaction handler, which the Firebase RealtimeDatabase library may call multiple times to apply changes to the data, and should return success or failure depending on whether it succeeds.

Note: This version of the callback is no longer supported (unless you are building for Android with stlport). You should use either one of DoTransactionWithContext (a simple function pointer that accepts context data) or DoTransactionFunction (based on std::function).See also:DoTransactionWithContext for more information.

Your own transaction handler function or lambda, which the Firebase RealtimeDatabase library may call multiple times to apply changes to the data, and should return success or failure depending on whether it succeeds.

See also:DoTransactionWithContext for more information.

Your own transaction handler, which the Firebase RealtimeDatabase library may call multiple times to apply changes to the data, and should return success or failure depending on whether it succeeds.

The context you specified to RunTransaction will be passed into this call.

This function will be called,possibly multiple times, with the current data at this location. The function is responsible for inspecting that data and modifying it as desired, then returning a TransactionResult specifying either that theMutableData was modified to a desired new state, or that the transaction should be aborted. Whenever this function is called, theMutableData passed in must be modified from scratch.

Since this function may be called repeatedly for the same transaction, be extremely careful of any side effects that may be triggered by this function. In addition, this function is called from within the Firebase RealtimeDatabase library's run loop, so care is also required when accessing data that may be in use by other threads in your application.

Best practices for this function are to ONLY rely on the data passed in.

Note: If you want a callback to be triggered when the transaction is finished, you can use the Future value returned by the method running the transaction, and callFuture::OnCompletion() to register a callback to be called when the transaction either succeeds or fails.See also:DoTransaction for more information.

Get the human-readable error message corresponding to an error code.

Get a server-populated value corresponding to the current timestamp.

When inserting values into the database, you can use the special valuefirebase::database::ServerTimestamp() to have the server auto-populate the current timestamp, which is represented as millieconds since the Unix epoch, into the field.

Compares twoQuery instances.

TwoQuery instances on the same database, in the same location, with the same parameters (OrderBy*, StartAt, EndAt, EqualTo, Limit*) are considered equivalent.

Equivalent Queries have a shared pool of ValueListeners and ChildListeners. When listeners are added or removed from oneQuery instance, it affects all equivalentQuery instances.

Compares twoDatabaseReference instances.