I just offered to do such a thing for the D of Ed.
In practice the approach is...
Does anyone actually want to know all the data. The answer is no.
In the D of Ed's case, the average parent just wants the truth, instead of spin. This is easy.
They could get by with about ten queries.
1. Which exams are worthless.
2. With a specific signature of "important to me" subjects, which school is best.
3. How much more could my children actually learn, if standards weren't downgraded to make less able children's parents think they've done well.
4. That's about it.
So instead of having "5 good gcses" etc. Schools would be ranked by other criteria.
One such would be to weight exams by difficulty, then come up with a perfect score value for all, then workout the best school for the year, and take the logarithm of the distance times away from this, that other schools were.