JPQL通過屬性列表

Question

我使用Spring的數據（JPA的存儲庫）中選擇，我有以下實體：

public class City{ 
    .... 
    private Street street; 
    .... 
} 

public class Street{ 
    ... 
    private List<Building> buildings; 
    ... 
} 

public class Building{ 
    ... 
    private List<Flat> flats; 
    .... 
} 

public class Flat{ 
    ... 
    private boolean lightsOn; 
    ... 
} 

我想創建一個查詢來獲取所有（不同）的城市有在至少有一個單位帶電燈。

我嘗試此查詢：

@Query("select distinct c from Cities c where c.street.buildings.flats.lightsOn = true") 

，但得到這個錯誤信息：

The state field path 'c.street.buildings.flats.lightsOn' cannot be resolved to a valid type. 

我怎麼能這樣做？

Answer 1

這是SQL代碼：

select * from city as c where c.idcity in 
    (select s.idcity from street as s where c.idcity = s.idcity and s.idstreet in 
     (select b.idstreet from building as b where b.idstreet = s.idstreet and b.idbuilding in 
      (select f.idbuilding from flat as f where f.idbuilding = b.idbuilding and f.lightsOn = 1) 
     ) 
    ) 

，如果你發現難以將其轉換爲JPQL只要告訴我:)。