mysql limit with inner join and subquery - mysql

Question

I have the following query:
SELECT saturday_combinations.index, v.val AS `row` , COUNT( * ) AS `count`
FROM saturday_combinations
INNER JOIN (
SELECT ONE AS val
FROM saturday_combinations
WHERE ONE IS NOT NULL
UNION
SELECT TWO AS val
FROM saturday_combinations
WHERE TWO IS NOT NULL
UNION
SELECT THREE AS val
FROM saturday_combinations
WHERE THREE IS NOT NULL
UNION
SELECT FOUR AS val
FROM saturday_combinations
WHERE FOUR IS NOT NULL
UNION
SELECT FIVE AS val
FROM saturday_combinations
WHERE FIVE IS NOT NULL
UNION
SELECT SIX AS val
FROM saturday_combinations
WHERE SIX IS NOT NULL
UNION
SELECT SEVEN AS val
FROM saturday_combinations
WHERE SEVEN IS NOT NULL
) v ON v.val = saturday_combinations.ONE
OR v.val = saturday_combinations.TWO
OR v.val = saturday_combinations.THREE
OR v.val = saturday_combinations.FOUR
OR v.val = saturday_combinations.FIVE
OR v.val = saturday_combinations.SIX
OR v.val = saturday_combinations.SEVEN
GROUP BY v.val
The purpose of the query is to provide a count of the different values contained in the columns ONE,TWO,THREE,FOUR,FIVE,SIX and SEVEN in the table saturday_combinations. However I want to put a desc limit 4 so that it only performs the count based on the last 4 rows (last four maximum indexes). But I am not getting it to work with the union. Adding order and limit at the very end only limits from the final select, rather than get the last 4 rows and calculate the distribution on them. Any tips?
The table schema is as follows:
index | ONE|TWO|THREE|FOUR|FIVE|SIX|SEVEN
1 1 3 7 10 11 12 13
2 3 4 5 30 31 22 23
3 1 2 3 4 5 6 7
4 1 2 3 4 5 6 7
5 1 2 3 4 5 6 7
6 1 2 3 4 5 6 7
7 1 2 3 4 5 6 7
8 1 2 3 4 5 6 7
9 1 2 3 4 5 6 7
10 1 2 3 4 5 6 7
Index is auto-increment and ONE-SEVEN has integer values.
There are about 3000 rows in the table and I want to count occurences for each value based on the last n rows.
Ideal result for the last n rows where n = last 3 rows should be
Numbers|Count
1 3
2 3
3 3
4 3
5 3
6 3
7 3
If I increase n to include last 6 rows their count should increase. If I could last 10 rows the count should increase and other numbers should appear with their count.
Here is a link to a sample of the real table.
http://sqlfiddle.com/#!2/d035b

Answer 1

If answer to my comment is yes then, you could try the following. When you need to add limit, order by to union selects you need to wrap union queries with brackets ().
SQLFIDDLE DEMO
Code:
(SELECT ONE AS val
FROM saturday_combinations
WHERE ONE IS NOT NULL
order by ONE desc limit 4)
UNION
(SELECT TWO AS val
FROM saturday_combinations
WHERE TWO IS NOT NULL
order by TWO desc limit 4)
UNION
(SELECT THREE AS val
FROM saturday_combinations
WHERE THREE IS NOT NULL
order by THREE desc limit 4)
If answer to my comment is no, then please clarify.
Here is the code based on your sample date:
select distinct x.one as uniqunumbers,
count(x.one) as counts
from(
sELECT DISTINCT 'one'
AS col1, one FROM sat_comb
UNION ALL
SELECT DISTINCT 'two'
AS col1, two FROM sat_comb
UNION ALL
SELECT DISTINCT 'three'
AS col1, three FROM sat_comb
) as x
group by x.one;
UNIQUNUMBERS COUNTS
1 1
3 2
4 1
5 1
7 1
EDIT as per OP has clarified and updated the question.
Quoted: "However I want to limit it so that it first takes the last n rows and then does the count on the values in those n rows. This means, if I have 3 columns with 3000 rows and 35 integers randomly appearing in these 3000 rows it should count how many times each integer appears."
SQLFIDDLE DEMO2
Query:
select x.one as uniqunumbers,
count(x.one) as counts
from(
(sELECT DISTINCT 'one'
AS col1, one FROM sat_comb
order by id desc limit 4)
UNION ALL
(SELECT DISTINCT 'two'
AS col1, two FROM sat_comb
order by id desc limit 4)
UNION ALL
(SELECT DISTINCT 'three'
AS col1, three FROM sat_comb
order by id desc limit 4)
UNION ALL
(SELECT DISTINCT 'four'
AS col1, four FROM sat_comb
order by id desc limit 4)
UNION ALL
(SELECT DISTINCT 'five'
AS col1, five FROM sat_comb
order by id desc limit 4)
UNION ALL
(SELECT DISTINCT 'six'
AS col1, six FROM sat_comb
order by id desc limit 4)
UNION ALL
(SELECT DISTINCT 'seven'
AS col1, seven FROM sat_comb
order by id desc limit 4)
) as x
group by x.one;
Output:
UNIQUNUMBERS COUNTS
2 4
3 3
4 3
5 4
6 4
8 3
9 4
20 3

Answer 2

Maybe I am missing something in your request but based on your desired result, why not just unpivot the data and perform the count.
select value, count(*) Total
from
(
select 'one' col, one value
from saturday_combinations
union all
select 'two' col, two value
from saturday_combinations
union all
select 'three' col, three value
from saturday_combinations
union all
select 'four' col, four value
from saturday_combinations
union all
select 'five' col, five value
from saturday_combinations
union all
select 'six' col, six value
from saturday_combinations
union all
select 'seven' col, seven value
from saturday_combinations
) src
group by value
See SQL Fiddle with Demo
The result of your sample is:
| VALUE | TOTAL |
-----------------
| 1 | 1 |
| 3 | 2 |
| 4 | 1 |
| 5 | 1 |
| 7 | 1 |
| 10 | 1 |
| 11 | 1 |
| 12 | 1 |
| 13 | 1 |
| 22 | 1 |
| 23 | 1 |
| 30 | 1 |
| 31 | 1 |
Edit #1: Based on your update this might be want you what:
select value, count(*)
from
(
select col, value
from
(
select 'one' col, one value
from saturday_combinations
order by one
limit 3
) one
union all
select col, value
from
(
select 'two' col, two value
from saturday_combinations
order by two desc
limit 3
) two
union all
select col, value
from
(
select 'three' col, three value
from saturday_combinations
order by three
limit 3
) three
union all
select col, value
from
(
select 'four' col, four value
from saturday_combinations
order by four
limit 3
) four
union all
select col, value
from
(
select 'five' col, five value
from saturday_combinations
order by five
limit 3
) five
union all
select col, value
from
(
select 'six' col, six value
from saturday_combinations
order by six
limit 3
) six
union all
select col, value
from
(
select 'seven' col, seven value
from saturday_combinations
order by seven
limit 3
) seven
) src
group by value
See SQL Fiddle with Demo
Result:
| VALUE | COUNT(*) |
--------------------
| 1 | 3 |
| 2 | 1 |
| 3 | 4 |
| 4 | 4 |
| 5 | 3 |
| 6 | 3 |
| 7 | 3 |

Answer 3

In case you want to look at the final solution:
http://sqlfiddle.com/#!2/867a6/13
Thanks to #bonCodigo for all the help