Wsrtjtyk

I have 2 Entities: User and Messages. Every User can have some Messages.

Class User

@Entity(tableName = DBConstants.TABLE_USER)

open class User(

        @field:PrimaryKey(autoGenerate = true)

        var id: Int = 0,

        var appUserId: Int = 0,

        var name: String = "",

        var phoneNumber: String = "",

        var appPackage: @AppPackage String = IN_APP,

        var userType: @UserType Int = CUSTOMER

) : Serializable ,BaseObservable(){

    @field:Ignore

    var messages: ArrayList<Messages> = ArrayList()



    @Bindable

    fun getNumMessages() : Int {

        return messages.size

    }

}

And Class Messages

@Entity(tableName = TABLE_USER_MESSAGES,

        foreignKeys = [ForeignKey(entity = User::class,

                parentColumns = arrayOf("id"),

                childColumns = arrayOf("userId"),

                onDelete = ForeignKey.CASCADE,

                onUpdate = ForeignKey.CASCADE)])

data class Messages(@field:PrimaryKey(autoGenerate = true) var id: Int = 0,

                    @field:ColumnInfo(name = "userId")

                    var userId: Int = 0,

                    var appUserId: Int = 0,

                    var appPackage: @AppPackage String = IN_APP,

                    var ticker: String = "",

                    var title: String = "",

                    var text: String = "",

                    var date : String)

For Select One User - Many Messages. I Created Class UserMessagesView.kt

class UserMessagesView {

    @Embedded

    var user : User = User()

    @Relation(parentColumn = "id", entityColumn = "userId",entity = Messages::class)

    var msg: List<Messages> = ArrayList()

}

I use Select Inner Join with Conditions follow this

@Dao

abstract class UserMessagesDao : BaseDao<Messages>() {

    @Query("SELECT * FROM user INNER JOIN messages ON messages.user_id = user.id WHERE messages.date like '%18-11-2018%'")

    abstract fun getAllMessagesByToday(): List<UserMessagesView>

}

In databse, I have 1 user in table users with id = 1
and 4 record messages in table messages foreign key with id user = 1. Follow 2 image
TableUser
[Table Messages][2]

My Issue is When I call method

getAllMessagesByToday

I received List is size = 4, But First element 'UserMessagesView ' object 'msg' have size = 4 and Others Element object 'msg' size = 0.
And object User in UserMessagesView in List They are the same all field and difference each ID
Follow Image Result

In this case I think Room will return 1 record containing a user object and a msg of 4 elements. But it's not exactly what I thought. And I do not know where I went wrong.
Please help me. It took me 3 days to find out but it did not work. Maybe Room is new and no one has problems like me. Thanks everyone.
Sorry my bad English.