Question

我的sql数据库中有3个表：

Table Room

roomnumber   roomtype    
  1           DeluxeRoom           
  2           DeluxeRoom  
  3           DeluxeRoom
  100         StandardRoom           
  101         StandardRoom  
  102         StandardRoom

房间是存放房间及其类型的桌子。

Table Reservation

reservationid  checkin       checkout
  1           2017-01-01     2017-01-03
  2           2017-01-10     2017-01-20
  3           2017-02-05     2017-02-08

预订是用户预订的表格。

Table RoomReserve

reservationid    roomnumber
 1                 1
 2                 100
 2                 101
 3                 1
 3                 2
 3                 3

在RoomReserve中，对于每个reservationid，我可以为roomnumber输入多个值。如果签入和结账日期不同，我也可以为不同的预订单输入相同的房间号。

我正在尝试在php中进行查询，以便在用户想要预订房间时计算可用的房间，但我得到的结果是错误的。

以下是我正在尝试的代码：

 1) $sql="SELECT COUNT(roomnumber) FROM room WHERE roomtype='DeluxeRoom'  AND roomnumber NOT IN ( 
SELECT * FROM roomreserve r,reservation e, room m  WHERE r.reservation_id=e.reservation_id AND m.roomnumber=r.roomnumber
AND ('$checkin' BETWEEN start_date AND end_date) OR ('$checkout' BETWEEN start_date AND end_date))"; 

2) $sql="SELECT COUNT(roomnumber) FROM room WHERE roomtype='DeluxeRoom'  AND roomnumber NOT IN ( 
SELECT COUNT(roomnumber) FROM roomreserve r,reservation e, room m  WHERE r.reservation_id=e.reservation_id AND m.roomnumber=r.roomnumber
AND ('$checkin' BETWEEN start_date AND end_date) OR ('$checkout' BETWEEN start_date AND end_date))";

Answer 1

如果客户目前已入住房间，您在结帐栏中有什么？如果它为空，那么您可以使用checkout is null进行查询，或者根据您的需要修改该部分。

select count(*) from room where roomtype = 'DeluxeRoom' and roomnumber not in (
select room.roomnumber from room, reservation, roomreserve where room.roomtype = 'DeluxeRoom' and roomreserve.roomnumber = room.roomnumber and roomreserve.reservationid = reservation.reservationid and checkout is null)

您还可以在Reservation表中添加checked_out标志，以便于查询。

Answer 2

在任何时候你都没有说你的内容有什么问题，但假设这个问题是语法上的（即你根本无法得到执行的语句），那就试试吧：

SET @start_date = '2017-01-01';
SET @end_date = '2017-01-10';
SELECT COUNT(roomnumber) FROM room WHERE roomtype='DeluxeRoom'  AND roomnumber NOT IN ( 
SELECT r.roomnumber FROM roomreserve r,reservation e, room m  WHERE r.reservationid=e.reservationid AND m.roomnumber=r.roomnumber
AND ((checkin BETWEEN @start_date AND @end_date) OR (checkout BETWEEN @start_date AND @end_date)));

至少那是一个有效的SQL语句。根据需要用PHP包装。

c＆amp; p easy的完整测试用例：

DROP TABLE Room;
DROP TABLE Reservation;
DROP TABLE RoomReserve;

CREATE TABLE Room (
    roomnumber int,
    roomtype varchar(255)
);

INSERT INTO Room
VALUES
    (1, 'DeluxeRoom'),
    (2, 'DeluxeRoom'),
    (3, 'DeluxeRoom'),
    (100, 'StandardRoom'),
    (101, 'StandardRoom'),
    (102, 'StandardRoom');


CREATE TABLE Reservation (
    reservationid int,
    checkin date,
    checkout date
);

INSERT INTO Reservation
VALUES
    (1, '2017-01-01', '2017-01-03'),
    (2, '2017-01-10', '2017-01-20'),
    (3, '2017-02-05', '2017-02-08');

CREATE TABLE RoomReserve (
    reservationid int,
    roomnumber int
);

INSERT INTO RoomReserve
VALUES
    (1, 1),
    (2, 100),
    (2, 101),
    (3, 1),
    (3, 2),
    (3, 3);


SET @start_date = '2017-01-01';
SET @end_date = '2017-01-10';

SELECT COUNT(roomnumber) FROM room WHERE roomtype='DeluxeRoom'  AND roomnumber NOT IN ( 
SELECT r.roomnumber FROM roomreserve r,reservation e, room m  WHERE r.reservationid=e.reservationid AND m.roomnumber=r.roomnumber
AND ((checkin BETWEEN @start_date AND @end_date) OR (checkout BETWEEN @start_date AND @end_date)));

我得到＆＃34; 2＆＃34;作为回应，这是在2017-01-01和2017-01-10（第2和第3房间）之间没有预订日期的DeluxeRoom的数量。

检查房间的可用性

2 个答案: