How to get monthly average active orders - mysql

Question

I have orders table which has the start date, end date and anticipated end date columns, I can able to get all the active work orders in month but I am looking for selected month average working orders.
I am trying to find an idea to get but unable to get, can someone please help on this?
SQL Fiddle
Updated Fiddle (Can we combine those 3 queries into single Query1+Query2-Query3 = desired count which is 7 in this case)
Updated as per the comments:
Average working means for example there are thousands of orders are in the database and some might close in the middle of the month and some might start in the start of the month some might start in the next month. So I want to know on average how many orders are working in the month.
Desired Result or Count is: 7, because 4 Orders are closed in the month and 4 are started in the month.
MySQL 5.6 Schema Setup:
CREATE TABLE `orders` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`order_num` BIGINT(20) NULL DEFAULT NULL,
`start_date` DATE NULL DEFAULT NULL,
`anticpated_end_date` DATE NULL DEFAULT NULL,
`end_date` DATE NULL DEFAULT NULL,
PRIMARY KEY (`id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB
AUTO_INCREMENT=1
;
INSERT INTO `orders` (`order_num`, `start_date`, `anticpated_end_date`, `end_date`) VALUES
('124267', '2019-01-11', '2020-01-10', '2020-01-10'),
('464335', '2019-01-03', '2019-11-15', '2019-12-13'),
('313222', '2019-01-03', '2020-02-15', NULL),
('63356', '2019-04-12', '2019-05-15', '2019-06-13'),
('235233', '2020-01-20', '2020-11-15', NULL),
('313267', '2019-01-03', '2020-01-15', '2020-01-19'),
('123267', '2019-12-10', '2020-07-31', NULL),
('234523', '2019-12-07', '2020-10-15', NULL),
('12344', '2020-01-03', '2020-02-15', NULL),
('233523', '2019-01-03', '2020-01-02', '2020-01-02'),
('233423', '2020-01-05', '2020-03-15', NULL),
('45644', '2020-01-11', '2020-08-15', NULL),
('233723', '2019-06-03', '2020-01-05', '2020-01-05'),
('345234', '2020-02-02', '2020-02-15', NULL),
('232423', '2020-02-03', '2020-03-15', NULL);
Query 1:
SELECT order_num, start_date, anticpated_end_date, end_date
FROM orders
WHERE start_date <= date("2020-01-31")
AND
(
(
end_date IS NULL AND
(
anticpated_end_date >= date("2020-01-31") OR
anticpated_end_date BETWEEN date("2020-01-01") AND date("2020-01-31")
)
) OR
(
end_date >= date("2020-01-31") OR
end_date BETWEEN date("2020-01-01") AND date("2020-01-31")
)
);

Answer 1

For the first query, I find this easier to read...
SELECT order_num, start_date, anticpated_end_date, end_date
FROM orders
WHERE start_date < '2020-01-01'
AND COALESCE(end_date,anticpated_end_date) > '2020-01-31';
If you're only interested in the count of that result, then consider the following...
SELECT SUM(start_date < '2020-01-01' AND COALESCE(end_date,anticpated_end_date) > '2020-01-31')n
FROM orders;
Does that help?

Answer 2

I am assuming that if the end date is marked as null then it is an active order else the order is not active.
So all active orders for month of Jan would be where end date is null and the start date is on or before 31 Jan 2020.
Based o above 2 assumptions the resulting query would look like this:
select order_num, start_date, end_date, anticpated_end_date
from orders
where end_date is null
and start_date <= date("2020-01-31")
order by start_date,end_date,anticpated_end_date;