Saving Data on Android

one-to-
many
 relations: The 
@Relation
 annotation.
@Relation
 is a very handy annotation that automatically retrieves records from 
related entities. You can apply it to a 
List
 or 
Set
  of objects and Room will take care 
of the rest for you. To see the 
@Relation
 in action, create a new class under the 
data 
▸
 model
 package and name it 
QuestionAndAllAnswers
.
Replace everything inside with the following:
class
 
QuestionAndAllAnswers
 { 
    
@Embedded
//1
 
    
var
 question: Question? = 
null
 
 
    
@Relation(parentColumn = "question_id",//2 
              entityColumn = "question_id")
 
    
var
 answers: List = ArrayList()
//3
 
}
Step by step:
1. Since you want to be able to access all the fields in the 
Question
 entity, we are 
using the 
@Embedded
 annotation to retrieve all the properties from that entity. If 
you need a reminder of how annotations like 
@Embedded
 work, take a look at the