Question

我希望将以下SQL转换为JPQL：

SELECT  *
FROM    rooms
WHERE   NOT EXISTS
(        
    SELECT  *
    FROM    booking, booking_has_rooms
    WHERE   rooms.number=booking_has_rooms.rooms_number AND 
            booking.booking_id=booking_has_rooms.booking_booking_id AND 
            :date BETWEEN booking.checkin AND booking.checkout
);

到目前为止，我有这个：

SELECT rooms 
FROM Rooms rooms 
WHERE NOT EXISTS 
(
    SELECT bk 
    FROM Booking b 
    JOIN  b.roomsCollection bk 
    WHERE :date BETWEEN b.checkin AND b.checkout
)

如果指定日期没有预订，则会正确返回所有房间。但是，如果在指定日期进行任何预订 - 它根本不会返回任何房间。

Answer 1

您在内部查询中缺少一个子句：

SELECT rooms 
FROM Rooms rooms 
WHERE NOT EXISTS 
(
    SELECT bk 
    FROM Booking b 
    JOIN  b.roomsCollection bk 
    WHERE :date BETWEEN b.checkin AND b.checkout
    and bk.id = rooms.id
)

如果您将Rooms重命名为Room，您的代码会更加清晰。每个实例都是一个单独的房间，所以它应该使用单数形式。

如何在JPQL中编写此SQL查询

1 个答案: