Saving Data on Android

Room Persistence 
Libraries
.
Understanding database schemas
The first step to creating an app that reads from a SQLite database is to decide on a 
database 
schema
. The schema is the formal declaration of how the data in a 
database is 
structured
. It is good practice to define constants that describe the 
database schema in a self-documenting way in their own class or file. These can be 
organized into subclasses for databases with multiple tables and should be visible 
throughout the scope of the project.
The schema you will define is going to create a database called 
todoitems.db
, with 
one table inside. Inside this table will be three columns:
1. The 
primary key
 column will be an auto incrementing 
Integer
 named