Question

我正在开发一种支持搜索和预订的酒店库存管理系统。我对该系统还很陌生，因此在编写查询以从清单中提取可用房间时需要帮助。

假设用户搜索包含以下值：

地区ID：1（例如，迪拜）入住日期：31-12-2018和退房日期：01-01-2019（该日期应在room_rate_types表的valid_from和valid_to之内，并且不应位于room_rate_type_blackout_dates表的from_date和to_date内，并且不应位于room_rate_type_booked_dates表的from_date和to_date，如果它位于room_rate_type_booked_dates表中，则应从room_types表的可用性列中减去已预订的（room_rate_type_booked_dates表）房间

成人1，儿童2，婴儿0：应在rooms_occupancy表中

我的搜索取决于下表，括号中提供了它们的相应列：

属性（region_Id），房间，rooms_occupancy（成人，儿童和婴儿），room_rate_types（可用性，valid_from和valid_to），room_rate_type_blackout_dates（从From_date到To_Date），room_rate_type_booked_dates（预订ID，From_date和to_Date）

properties ( stores the general details of the property)
  pk property_id(primary key)
  region_id (id of the region)
  property_name


rooms ( stores the general details of the rooms)
  pk room_id(primary key)
  fk rooms_occupancy_id (the combination of the occupancies associated with the room)

rooms_occupancy  ( stores the general details of the combination of the 
                   occupancies in a single room)
  pk room_occupancy_id(primary key)
  fk room_id(foreign key that references the room table)
  adult,
  child,
  infant

room_rate_types (stores of the general details of the rates per room)
  pk rate_id(primary key)
  valid_from, 
  valid_to, 
  available_rooms
  fk room_id


room_rate_type_blackout_dates (stores the black out dates per rate)
  pk rate_blk_date_id (primary key)
  from_date, 
  to_date, 
 fk  rate_id (rate_id of the room_rate_types table)

room_rate_type_booked_dates (stores the booking info of the rate table)
  pk booking_id (primary key)
  from_date, 
  to_date, 
  fk rate_id (rate_id of the room_rate_types table)
  booked_rooms

预期结果应如下所述：

PropertyId, rateId, roomId, availblerooms 
1              1     1          5

Answer 1

我已尝试根据您的描述创建您的方案。它可以工作，但是可能会导致您对我所做的事情和您想做的事情提出更多疑问：

设置：

Create Table properties 
(
  property_id Int,
  region_id Int,
  property_name VarChar(25),
  room_id Int
)
Insert Into properties Values
(1,1,'property1',1)

Create Table rooms
(
  room_id Int,
  rooms_occupancy_id Int, --(the combination of the occupancies associated with the room)
)
Insert Into rooms Values
(1,1)

Create Table rooms_occupancy  --( stores the general details of the combination of the occupancies in a single room)
(
  room_occupancy_id Int,
  adult Int,
  child Int,
  infant Int
)
Insert Into rooms_occupancy Values
(1,1,2,0)

Create Table room_rate_types --(stores of the general details of the rates per room)
(
  rate_id Int,
  valid_from Date, 
  valid_to Date, 
  available_rooms Int,
  rate_blk_date_id Int, 
  booking_id Int
)
Insert Into room_rate_types Values
(1,'2018-12-31','2019-01-01',6,1,1)

Create Table room_rate_type_blackout_dates --(stores the black out dates per rate)
(
  rate_blk_date_id Int,
  from_date Date, 
  to_date Date, 
  rate_id Int
)
Insert Into room_rate_type_blackout_dates Values
(1,'2018-12-29','2018-12-30',1)

Create Table room_rate_type_booked_dates --(stores the booking info of the rate table)
(
  booking_id Int  IDENTITY(1,1) NOT NULL,
  from_date Date, 
  to_date Date, 
  rate_id Int,
  booked_rooms Int
)

程序：

Declare @From As Date = '2018-12-31'
Declare @To As Date = '2019-01-01' 

Declare @property As Int = 1
Declare @Region As Int = 1

Declare @roomratetypeid As Int = 1

If Exists 
(
   SELECT        
      p.property_id, 
      p.room_id,
      rate_id = (Select rate_id From room_rate_types Where rate_id = @roomratetypeid),
      Availablerooms = (Select available_rooms From room_rate_types Where rate_id = @roomratetypeid) - 1
   FROM 
      properties p INNER JOIN
      rooms r ON p.room_id = r.room_id INNER JOIN
      rooms_occupancy ro ON r.rooms_occupancy_id = ro.room_occupancy_id
   Where   
      p.property_id = @property And
      p.region_id = @Region And
      (  --Check if requested dates are available
         @From >= (Select valid_from From room_rate_types Where rate_id = @roomratetypeid) And
         @To  <= (Select valid_to From room_rate_types Where rate_id = @roomratetypeid)
      ) And
      Not Exists (Select booking_id From room_rate_type_booked_dates Where @From >= from_date And @To <= to_date) And
      Not Exists (Select rate_blk_date_id From room_rate_type_blackout_dates  Where @From >= from_date And @To <= to_date) 
)  --If NOT exists, create booking and display results and adjust the available rooms
Begin
      SELECT        
      p.property_id, 
      p.room_id,
      rate_id = (Select rate_id From room_rate_types Where rate_id = @roomratetypeid),
      Availablerooms = (Select available_rooms From room_rate_types Where rate_id = @roomratetypeid) - 1
   FROM 
      properties p INNER JOIN
      rooms r ON p.room_id = r.room_id INNER JOIN
      rooms_occupancy ro ON r.rooms_occupancy_id = ro.room_occupancy_id
   Where   
      p.property_id = @property And
      p.region_id = @Region And
      (  --Check if requested dates are available
         @From >= (Select valid_from From room_rate_types Where rate_id = @roomratetypeid) And
         @To  <= (Select valid_to From room_rate_types Where rate_id = @roomratetypeid)
      )
   Update room_rate_types Set available_rooms = (Select available_rooms From room_rate_types Where rate_id = @roomratetypeid) - 1;
   Insert Into room_rate_type_booked_dates Values (@From,@To,@roomratetypeid,1)
End
Else 
   Select 'Not Available';

结果：

property_id room_id rate_id Availablerooms
1           1       1       5

查询以从清单中检索可用房间

1 个答案: