UserDao.kt

@Dao
interface UserDao{

    @Query("SELECT * FROM users_table")
    fun getAll():List<User>

    @Query("SELECT * FROM users_table WHERE Id = :Id")
    fun getUser(Id:Long): User

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    fun insert(user: User)

    @Delete()
    fun delete(user: User)

    @Update
    fun update(user: User)

    @Query("DELETE FROM users_table")
     fun deleteAll()

}