Programming is math. The numbers are just wearing different clothes.
Forum DOs and DON'Ts
Never assume that information you find using a search engine is up-to-date.
The same can apply to the transformation of those rows into output rows. You have to formulate your expectations that the program would indeed yield a correct output row for every selected input row. You also had to demonstrate that your program would execute correctly even in the absence of rows, and that demonstration preferably had to take place before you released your program into the production environment.
It's not linear algebra or arithmetics, but it can be considered Math, nonetheless.