hotel booking check empty room between arrival date and departure date?

Question

Basically i retrieve all available room with arrival and departure date from the room table.

SQL Query

SELECT * FROM `roomcalendar` where day BETWEEN '2016-08-25' and '2016-08-31'

Result is

id day        roomname avaroom
 1 2016-08-25 RoomA          0
 2 2016-08-26 RoomA          2
 3 2016-08-27 RoomA          0
 4 2016-08-28 RoomA          1
 5 2016-08-29 RoomA          1
 6 2016-08-30 RoomA          0
 7 2016-08-31 RoomA          1

I just want available room if avaroom not equal to 0 beteen arrival date and departure date

And I want the result

SQL Query

SELECT * FROM `roomcalendar` where day BETWEEN '2016-08-25' and '2016-08-31'

it must be empty result

SQL Query

 SELECT * FROM `roomcalendar` where day BETWEEN '2016-08-25' and '2016-08-26'

it must be empty result

SQL Query

 SELECT * FROM `roomcalendar` where day BETWEEN '2016-08-26' and '2016-08-27'

it show one result

SQL Query

SELECT * FROM `roomcalendar` where day BETWEEN '2016-08-26' and '2016-08-28'

it must be empty result

SQL Query

SELECT * FROM `roomcalendar` where day BETWEEN '2016-08-28' and '2016-08-30'

it show two result

Thanks.

Answer 1

I just want available room if avaroom not equal to 0 beteen arrival date and departure date

So if you reformulate this:

• you want the room if there is no row where avaroom = 0 between two dates.

Translated in SQL:

select * from roomcalendar
where day between '2016-08-25' and '2016-08-31'
and not exists (
  select * from roomcalendar
  where day between '2016-08-25' and '2016-08-31'
  and avaroom = 0
);

You can also reformulate by saying:

• you want the room if the number of rows where avaroom is not 0 is the total number of rows expected (in this case, this corresponds to the amount of days)

Translated in SQL:

select * from roomcalendar
where day between '2016-08-25' and '2016-08-31'
and avaroom != 0
having count(*) = datediff('2016-08-31','2016-08-25') + 1

You might have to tweak the queries a bit, but that should point you to the right direction.

Answer 2

Modify the query like this.

SELECT * FROM `bookings` WHERE `room_id` = '1' 
AND booking_end >= '2020-12-01 13:20:00' AND booking_start <= '2020-12-10 13:20:00'