Count with Having didn't return anything - mysql

Question

I'm curious about how to write the correct query when I wanna use count function with having clause..
So I have a table named : seat
and here are the columns:
SEAT
ID_SEAT ID_TIME STATUS
-----------------------------------------
A1 | 1 | Available
A2 | 2 | Available
A3 | 1 | Available
A4 | 1 | Reserved
And so on.
I have 119 rows which the status is 'Available' and 1 row which the status is 'Reserved'.
And here is the query in MySQL:
SELECT status, COUNT(status) AS number FROM seat
WHERE ID_SEAT = 'A3' AND ID_TIME = '1'
HAVING COUNT(status) IN (SELECT COUNT(status) from SEAT where status = 'Available')
But the query didn't show anything..Any help and clear answer would be very helpful ..thank you :)
EDIT :
What I really want to display is something like this :
STATUS NUMBER
---------------------
Available 119
The STATUS field above is for a certain ID_SEAT...in my case the ID_SEAT = 'A3' and for ID_TIME = 1
EDITTTTT :
thank you for all the answer to me..
Now I can fix it clearly..
So I'm using "UNION" to separate the query..I'm using 2 queries to make it works..
here the code :
SELECT status from seat where ID_SEAT = 'A3' AND ID_TIME = '1' UNION
SELECT COUNT(status) from seat
where status = 'Available'
however the code above is work for mysql query.. thank you a lot :)

Answer 1

if you want your result like the one you showed.
SELECT status, COUNT(status) as number
FROM seat
WHERE status = 'Available'
GROUP BY status
If you wanted to see status of seat then simply select status, no need for count
SELECT status
FROM seat
WHERE ID_SEAT = 'A3' AND ID_TIME = '1'
If you must, return status of seat and a count of ALL available seats
SELECT status,(SELECT count(*) FROM seat WHERE status = 'Available') as number
FROM seat
WHERE ID_SEAT = 'A3' AND ID_TIME = '1'

Answer 2

Any time you use an aggregate function like count, sum, avg etc... in the select part of the query, as well as a non aggregate function--"status" in this case--you MUST have a "group by" clause.
So it would look like this:
SELECT status, COUNT(status), AS number FROM seat
HAVING COUNT(status) IN (SELECT COUNT(status) FROM SEAT WHERE status = 'Available')
GROUP BY status
This will make it so you see two rows. One for available with a count of 119, and one for reserved with a count of 1.

Answer 3

In your query, the expression (SELECT COUNT(status) from SEAT where status = 'Available') is going to return 119. However, you are only selecting one row, so the two values can never be equal.
I think you want:
SELECT status, COUNT(status) AS number
FROM seat
GROUP BY status;
This will return all status. If you really only want 'Available', then filter using a where:
SELECT status, COUNT(status) AS number
FROM seat
WHERE status = 'Available';
EDIT: (Based on clarification in comment)
Oh, if you only want the status information for seat number 23, you can get that with a having clause:
SELECT status, COUNT(status) AS number
FROM seat
GROUP BY status
HAVING sum(id_seat = '23A') > 0;
The having clause is counting up the number of rows, for each status, where the id_seat has a value of 23. You want the status where there is at least one row, which is what the having clause does.