Get most occured value in the table - mysql

Question

I got following tables
1. user
+----+-------------------+
| id | email |
+----+-------------------+
| 2 | user1#example.com |
| 3 | user2#example.com |
| 1 | user3#example.com |
+----+-------------------+
2. answer
+----+---------+-------------+-----------+---------------------+
| id | user_id | question_id | option_id | created |
+----+---------+-------------+-----------+---------------------+
| 1 | 2 | 1 | 5 | 2015-12-19 15:15:07 |
| 2 | 2 | 1 | 5 | 2015-12-19 15:16:05 |
| 3 | 2 | 2 | 3 | 2015-12-19 15:16:06 |
| 4 | 2 | 3 | 3 | 2015-12-19 15:16:08 |
| 5 | 2 | 1 | 1 | 2015-12-19 15:32:46 |
| 6 | 2 | 1 | 4 | 2015-12-19 15:39:22 |
| 7 | 2 | 1 | 2 | 2015-12-19 15:39:23 |
| 8 | 2 | 1 | 2 | 2015-12-19 15:40:38 |
| 9 | 2 | 1 | 1 | 2015-12-19 15:41:25 |
+----+---------+-------------+-----------+---------------------+
I want to fetch option_id with most occurrences grouped by user with the following condition
If there are two or more maximum occurrences of option_id, get last record.
With reference to above answer table, as you see there are four maximum occurrences for option_id, in this case i want last in the list to be returned which is option_id 1
Here is the query i used to achieve what i want
SELECT
option_id,
COUNT(option_id) as occurence
FROM
answer
GROUP BY
option_id
ORDER BY
occurence DESC LIMIT 1;
This works, however when i add WHERE condition, it gives me option_id 5, whereas i expect option_id 1
SELECT
option_id,
COUNT(option_id) as occurence
FROM
answer
WHERE
user_id = 2
GROUP BY
option_id
ORDER BY
occurence DESC LIMIT 1;
What am i missing here?
Note : This is a follow-up question from this link, the reason i am re-posting here is to post simplified version of the same question.

Answer 1

I did something similar on my tables, and that's my solution:
SELECT option_id
FROM answer
WHERE id = (SELECT id
FROM answer
WHERE user_id = 2
GROUP BY option_id
ORDER BY COUNT(option_id) DESC, id DESC
LIMIT 1)
Or see what happens if you do ORDER BY occurence DESC, id DESC in your query.

Answer 2

If it's really only the order_id you are interested in, you can simply add MAX(created) DESC to your ORDER BY:
SELECT
option_id,
COUNT(option_id) as occurence
FROM
answer
WHERE
user_id = 2
GROUP BY
option_id
ORDER BY
occurence DESC, MAX(created) DESC LIMIT 1;

Answer 3

Step by step:
Count option_id occurrences (group by option_id and count)
Get maximum count from above figures (with max or with order by and limit 1)
3, Get all option_id with this count.
Get all records with one of those option_ids.
Keep only the last record of the this found records (order by limit 1).
Query:
select *
from answer
where option_id in
(
select option_id
from answer
group by option_id
having count(*) =
(
select count(*) as cnt
from answer
group by option_id
order by count(*) desc limit 1
)
)
order by created desc limit 1;