Saving Data on Android

Chapter 13: Reading to and 
writing from Realtime Database
 you'll learn a lot more about reading from and 
writing to Realtime Database and you'll integrate it to the WhatsUp app. You'll be 
able to write posts from the app and upload it to the Realtime Database and other 
users will be able to read it.
Saving Data on Android
Chapter 12: Introduction to Firebase Realtime Database
raywenderlich.com
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Chapter 13: Reading to & 
Wri/ng from Real/me 
Database
By Dean Djermanović
In the last chapter, you integrated Realtime Database into your app. You added 
Firebase SDK to your app and connected the app with Firebase project. You also 
learned about database rules and you set them up to allow only authenticated users 
the access to the database. You even wrote your first data to the database which was 
just a sneak peek of what you'll do in this chapter.
This chapter will teach you how to work with Realtime Database data. You'll learn 
how to read and write data as well as how to do basic manipulation with that data. 
First, you'll learn about performing 
CRUD
 operations on to the Realtime Database. 
CRUD is just an acronym for the four basic types of SQL commands: 
Create
, 
Read
, 
Update
, 
Delete
. You'll combine all these concepts together in order to build a fully 
functional app with Realtime Database as the backend.
Note
: You need to set up Firebase in order to follow along. Do the following 
steps:
1. Create a project in the Firebase console.
2. Enable Google sign-in.
3. Set security rules to the test mode to allow everyone