SQL - Find Available Slots Within Date Range - mysql

Question

I have following database schema:
CREATE TABLE `property` (
`id` INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,
`name` VARCHAR(100) NOT NULL
);
CREATE TABLE `venue` (
`id` INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,
`property_id` INT(11) NOT NULL,
`name` VARCHAR(100) NOT NULL
);
CREATE TABLE `venue_available` (
`id` INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,
`venue_id` INT(100) NOT NULL,
`day` VARCHAR(10) NOT NULL,
`from_time` TIME NOT NULL,
`to_time` TIME NOT NULL,
`lead_time_in_minutes` INT(11)
);
CREATE TABLE `venue_unavailable` (
`id` INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,
`venue_id` INT(100) NOT NULL,
`from_datetime` DATETIME NOT NULL,
`to_datetime` DATETIME NOT NULL
);
CREATE TABLE `venue_reservation` (
`id` INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,
`venue_id` INT(100) NOT NULL,
`start_datetime` DATETIME NOT NULL,
`end_datetime` DATETIME NOT NULL
);
I want to find properties having venues available from 25th Aug(Sat) to 27th August (Mon) from 10am to 3pm
Here is the SQL query I tried
SELECT
p.id,
p.name AS property_name,
v.name AS venue_name
FROM
venue v
LEFT JOIN
property p ON v.property_id = p.id
-- venue_available
LEFT JOIN
venue_available va_0 ON va_0.venue_id = v.id
LEFT JOIN
venue_available va_1 ON va_1.venue_id = v.id
WHERE 1 = 1
-- venue_available
AND (
(va_0.day = 'sat' AND va_0.from_time <= '2018-08-25 10:00:00' AND va_0.to_time >= '2018-08-25 15:00:00') AND
(va_1.day = 'sun' AND va_1.from_time <= '2018-08-26 10:00:00' AND va_1.to_time >= '2018-08-26 15:00:00')
)
-- venue_unavailable
AND NOT EXISTS (SELECT * FROM venue_unavailable vu WHERE '2018-08-25 10:00:00' <= vu.to_datetime AND '2018-08-26 15:00:00' >= vu.from_datetime)
GROUP BY
p.id;
The problem with the current query is, the condition for venue_available in SQL query seems to work correctly, but when I add the condition for venue_unavailable it returns me the empty result, however based on the data I am expecting 1 result.
Here is the link to SQL fiddle, if you want to play around with schema and fixtures
http://sqlfiddle.com/#!9/33d60f/10
Here is what I am trying to do
1. Get the list of all properties (not venues)
2. List the property only if one or more venue is available after checking with
venue_available
venue_unavailable
venue_reservation
Can you help me with how to go about this?x
Thank you.
UPDATE1
I followed the following post to determine overlapping dates in venue_unavailable Select rows that are not between dates (reservation)

Answer 1

Alright, so the way I solved it is using sub query which is working now.
I am now using the WHERE clause with something like this
WHERE v.id NOT IN (SELECT venue_id FROM provider_block pb WHERE :start_datetime <= pb.to_date AND :end_datetime >= pb.from_date)
This seems to do the job for now.