【Spring】Spring JPQLで結合する場合に気をつけること【JPQL】

package com.example.demo.repository;

import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;

import com.example.demo.entity.Room;

public interface RoomRepository extends JpaRepository<Room, Integer> {

    @Query("SELECT r FROM Room r LEFT OUTER JOIN r.equipments")
    List<Room> find();
}

①Roomテーブルのselect 
select
　r1_0.room_id,
　r1_0.invalid,
　r1_0.room_name 
from
  room r1_0 left join　equipment e1_0 on r1_0.room_id=e1_0.room_id

②①で取得したRoomテーブルのレコードのうち、
Equipmentテーブルに紐づくレコードがある場合、都度selectを行う。

select
　e1_0.room_id,
　e1_0.equipment_id,
　e1_0.equipment_name,
　e1_0.invalid 
from
  equipment e1_0 
where
 　e1_0.room_id=?

binding parameter [1] as [INTEGER] - [1]

select
　e1_0.room_id,
　e1_0.equipment_id,
　e1_0.equipment_name,
　e1_0.invalid 
from
  equipment e1_0 
where
 　e1_0.room_id=?

binding parameter [1] as [INTEGER] - [2]

select
　e1_0.room_id,
　e1_0.equipment_id,
　e1_0.equipment_name,
　e1_0.invalid 
from
  equipment e1_0 
where
 　e1_0.room_id=?

binding parameter [1] as [INTEGER] - [3ｋ]

package com.example.demo.repository;

import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;

import com.example.demo.entity.Room;

public interface RoomRepository extends JpaRepository<Room, Integer> {

    @Query("SELECT r FROM Room r LEFT OUTER JOIN FETCH r.equipments")
    List<Room> find();
}

select
  r1_0.room_id,
  e1_0.room_id,
  e1_0.equipment_id,
  e1_0.equipment_name,
  e1_0.invalid,
  r1_0.invalid,
  r1_0.room_name 
from
  room r1_0 left join equipment e1_0 
  on r1_0.room_id=e1_0.room_id