Query to get categorised sets of splits - mysql

Question

Given this table structure:
CREATE TABLE IF NOT EXISTS splits (
id INT AUTO_INCREMENT,
sector_id INT,
type VARCHAR(100),
percentage INT,
PRIMARY KEY (id),
INDEX (type)
) ENGINE MyISAM;
And this data set:
INSERT INTO splits (sector_id, type, percentage) VALUES
(1, 'Manager', '50'),
(1, 'Sales Rep', '50'),
(2, 'Manager', '75'),
(2, 'Sales Rep', '25'),
(3, 'Manager', '75'),
(3, 'Sales Rep', '25'),
(4, 'Manager', '100'),
(5, 'Manager', '100'),
(6, 'Manager', '100');
How could I return the amount of sectors that split in the same way:
Like this:
Split | Number
---------------+-------
50% M / 50% SR | 1
75% M / 25% SR | 2
100% M | 3
So this shows 1 sector (id 1) has a split ratio of 50/50, 2 sectors have a split ratio of 75/25 (ids 2, 3) and 3 sectors have a split ratio off 100/0 (ids 4, 5, 6).
Here is a SQL Fiddle with the database setup: http://sqlfiddle.com/#!2/6b19f/1
What have you tried?
I cannot even think of where to start to solve this problem, so I apologise for not being able to show an attempted solution. I will update this question if I get anywhere.
The reason why I want to do this all in the database (and not the application) is because our automated reporting tools can be pointed to a table/view/query and automatically apply filtering, sorting, charting etc. To do it manually in the application loses all the default functionality.

Answer 1

I don't really understand the problem. Your DB contains already all the data you want to retrieve?!
SELECT
sector_id AS Number,
type
percentage
FROM
splits
The easiest thing would now to take you software and then turn those (type-percentage)-tuples into strings. Why do you need the database to create and concat this string?
Can there be more than 2 types?
For Postgres I'd use an array of tuples for output:
SELECT
sector_id,
array_agg(row(percentage, type))
FROM
splits
GROUP BY
sector_id
Correct Query:
SELECT
x.y,
COUNT(*) c
FROM (
SELECT
sector_id,
GROUP_CONCAT(CONCAT(percentage, '% '), type SEPARATOR ' / ') AS y
FROM (
SELECT
sector_id,
type,
percentage
FROM splits
ORDER BY sector_id, type
) z
GROUP BY sector_id
) x
GROUP BY x.y
ORDER by c
Result will look like this:
50% Manager / 50% Sales Rep | 1
75% Manager / 25% Sales Rep | 2
100% Manager | 3