MySQL - выбор всех номеров, включая частичные диапазоны дат

Question

В настоящее время у меня есть наличие свободных номеров, которое отображает текущие открытые номера для бронирования с указанным диапазоном дат.

Мне нужно отобразить ту же доступность, но вместо отображения номеров для полной доступности мне нужно показать частичную доступность ,

Eg: booking 1 is from dates 22nd to 25th (within room 4)
booking 2 is from dates 24th to 28th (within room 3)
queried booking is from 23rd till 25th

22nd    23rd  24th     25th      28th
|-----------------------|
               |------------------|
        |------|                    free space

запрос:

SELECT r.*
     , CASE WHEN b.ref IS NULL THEN 'all' ELSE 'partial' END status
  FROM roominfo r 
  LEFT JOIN bookroom br ON br.id = r.id 
  LEFT JOIN book b ON b.ref = br.ref 
  AND b.end_date >= '2019-11-23' AND b.start_date <= '2019-11-25'
 ORDERBY r.id;         

пример структуры и данных:

 CREATE SCHEMA TEST;
USE TEST;

CREATE TABLE BOOK( Ref INT NOT NULL AUTO_INCREMENT, Start_Date DATE NOT NULL, End_Date DATE NOT NULL, PRIMARY KEY(Ref));
CREATE TABLE ROOMINFO( ID INT NOT NULL AUTO_INCREMENT, `Type` VARCHAR(10) NOT NULL, Max TINYINT NOT NULL, PRIMARY KEY(ID));
CREATE TABLE BOOKROOM( Ref INT NOT NULL,ID INT NOT NULL, FOREIGN KEY (Ref) REFERENCES BOOK(Ref), FOREIGN KEY (ID) REFERENCES ROOMINFO(ID));

INSERT INTO BOOK(Start_Date, End_Date) VALUES   
('2019-11-22', '2019-11-25'),('2019-11-24', '2019-11-28'),('2019-12-01', '2019-12-02'),('2019-12-01', '2019-12-06'),
('2019-12-02', '2019-12-03'),('2019-12-04', '2019-12-10'),('2019-12-04', '2019-12-10'),('2019-12-05', '2019-12-13'),
('2019-12-16', '2019-12-19'),('2019-12-26', '2019-12-28'),('2019-12-26', '2020-01-01'),('2019-12-28', '2020-01-02'),
('2019-12-31', '2020-01-05'),('2020-01-03', '2020-01-08'),('2020-01-05', '2020-01-11'),('2020-01-06', '2020-01-09'),
('2020-01-06', '2020-01-11'),('2020-01-08', '2020-01-18'),('2020-01-11', '2020-01-15'),('2020-01-15', '2020-01-17'),
('2020-01-15', '2020-01-18');

INSERT INTO ROOMINFO (ID, `Type`,Max) VALUES
(1, "Family", 4), (2, "Family", 4), (3, "Family", 4), (4, "Dual", 2),
(5, "Dual", 2),   (6, "Dual", 2), (7, "Dual", 2),   (8, "Dual", 2),
(9, "Dual", 2),   (10, "Dual", 2);

INSERT INTO BOOKROOM( Ref, ID ) VALUES
(1, 4), (2, 3), (3, 4), (4, 5),(5, 6), (6, 7), (7, 3), (8, 2), (9, 1), (10, 8),(11, 3), 
(12, 9), (13, 2), (14, 10), (15, 4), (16, 5), (17, 6), (18, 7), (19, 2),(20, 1), (21, 10);

желаемый вывод:

id    (& some indication of partial availability?)
1  all
2  all
3  partial
4  partial
5  all
6  all
7  all
8  all
9  all
10  all

Answer 1

Игнорирование печальной политики именования ...

DROP TABLE IF EXISTS book;

CREATE TABLE BOOK( Ref INT NOT NULL AUTO_INCREMENT, Start_Date DATE NOT NULL, End_Date DATE NOT NULL, PRIMARY KEY(Ref));

DROP TABLE IF EXISTS roominfo;
CREATE TABLE ROOMINFO( ID INT NOT NULL AUTO_INCREMENT, `Type` VARCHAR(10) NOT NULL, capacity TINYINT NOT NULL, PRIMARY KEY(ID));

DROP TABLE IF EXISTS bookroom;
CREATE TABLE BOOKROOM( Ref INT NOT NULL,ID INT NOT NULL);

INSERT INTO BOOK(Start_Date, End_Date) VALUES   
("2019-11-03", "2019-11-10"), ("2019-11-05", "2019-11-13");

INSERT INTO ROOMINFO (ID, `Type`,capacity) VALUES
(1, "Family", 4), (2, "Family", 4), (3, "Family", 4), (4, "Dual", 2),
(5, "Dual", 2),   (6, "Dual", 2), (7, "Dual", 2),   (8, "Dual", 2),
(9, "Dual", 2),   (10, "Dual", 2);

INSERT INTO BOOKROOM( Ref, ID ) VALUES (1, 4), (2, 3);

SELECT r.*
     , CASE WHEN b.ref IS NULL THEN 'all' ELSE 'partial' END status
  FROM roominfo r 
  LEFT 
  JOIN bookroom br 
    ON br.id = r.id 
  LEFT 
  JOIN book b 
    ON b.ref = br.ref 
   AND b.end_date >= '2019-11-01' AND b.start_date <= '2019-11-13'
 ORDER
    BY r.id;
+----+--------+----------+---------+
| ID | Type   | capacity | status  |
+----+--------+----------+---------+
|  1 | Family |        4 | all     |
|  2 | Family |        4 | all     |
|  3 | Family |        4 | partial |
|  4 | Dual   |        2 | partial |
|  5 | Dual   |        2 | all     |
|  6 | Dual   |        2 | all     |
|  7 | Dual   |        2 | all     |
|  8 | Dual   |        2 | all     |
|  9 | Dual   |        2 | all     |
| 10 | Dual   |        2 | all     |
+----+--------+----------+---------+