Well, it is a design question, I think that not relevant for the solution.

The column "a" is a score calculated from an algorithm.
The user usually only needs to see the first page, never the page 237232.
The column "b" is a name. When several records have the same score, the second order is the name.

It is similar (not equal) than google.com, results are ordered by score or ranking, the user only needs the see the first or second page.

In few words, a process calculates the score of each record and the user wants to see the top 10 records. Remaining records can be ignored.

I can use a computed field, I know, and the problem is solved, but I wanted to find how to create a mixed index in FB.

Thank you

> You have mentioned that several times, to which my reply was:
>
> Why do you want the first 10 (or second 10 or whatever) rows of MILLIONS
> of rows? Because you want to "page" them? What user wants to go to page
> 237232 of this list?
>
> >