Using multiple parameters invoking custom column

Hey there!

So I've got following issue:

I'm fetchting tables from a website. So far so good, but these are categorized into different categories which can be parameterized in the URL. Also those tables have multiple pages, which also can be parameterized in the URL.

I created a table for the categories to use a function to invoke all tables on the categories on a flat table basis.

I also created a list for the pages {1..100} so that I can also use a function to "iterate" over those.

I'm able to invoke the tables to categories, also the tables to the page numbers.

But where I fail is to get both steps in one query. I haven't been able to succeed over two steps - doing one thing and then the other - because I can't expand a function. 

I feel like drawing a blank. Someone please have mercy and help me here 🙂