The document discusses various data storage options in Android, including shared preferences, internal and external storage, SQLite databases, and network connections. It highlights the importance of content providers for data management and synchronization, allowing applications to access and modify shared data securely. Additionally, the document addresses the challenges of ensuring consistent data across different devices and the fundamental CRUD operations associated with content providers.

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Storing and Retrieving Data
Chapter Four
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Introduction
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 Android provides several options for you to save persistent application
data.
 The solution you choose depends on your specific needs, such as
whether the data should be private to your application or accessible to
other applications (and the user) and how much space your data
requires.

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 Your data storage options are the following:
Shared Preferences
Store private primitive data in key-value pairs.
Internal Storage
Store private data on the device memory.
External Storage
Store public data on the shared external storage.
SQLite Databases
Store structured data in a private database.
Network Connection
Store data on the web with your own network server.

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 Android provides a way for you to expose even your private data to
other applications — with a content provider.
 Using the External Storage
Every Android-compatible device supports a shared “external storage” that
you can use to save files.
 Using Databases
Android provides full support for SQLite databases. Any databases you
create will be accessible by name to any class in the application, but not
outside the application.

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 Using a Network Connection
You can use the network (when it’s available) to store and retrieve data on
your own web-based services. To do network operations, use classes in the
following packages:
java.net.*
android.net.*

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 Synchronization and Replication of Mobile Data
 Data synchronization is a method of establishing consistency among
data from a data source to the target data storage and vice versa.
 In data synchronization, we have to keep multiple copies of a dataset
in coherence with one another to maintain the data integrity.

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 Getting the Model Right
 Every business wants to provide services to their customers, wherever
they are and whatever they are doing. Some do this through their
website; others do use a mobile app.
 The challenge is that there is a multitude of different devices used by
customers.
 So which devices should the app be supported on? Can all be
supported?

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 Working with a Content Provider
 In Android, Content Providers are a very important component that
serves the purpose of a relational database to store the data of
applications.
 The role of the content provider in the android system is like a central
repository in which data of the applications are stored, and it facilitates
other applications to securely access and modifies that data based on
the user requirements.
 Users can manage to store the application data like images, audio,
videos, and personal contact information by storing them in
SQLite Database, in files, or even on a network.

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Operations in Content Provider
 Four fundamental operations are possible in
Content Provider namely Create, Read, Update,
and Delete. These operations are often termed
as CRUD operations.
 Create: Operation to create data in a content
provider.
 Read: Used to fetch data from a content
provider.
 Update: To modify existing data.
 Delete: To remove existing data from the
storage.

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THANK YOU
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