Copy and paste this snippet into a flow to get started.
parabola:cb:47ed9ba4189941818c5d6db44edca605
It’s a tricky problem that took more steps than I’d like, but it should work for you.
This toggle explains how the flow works, if you're interested.
Essentially, this snippet takes a CSV with two columns, as you described, and splits the values into two separate tables, one for each column. Then it splits the “a,b,c” values into three separate columns. Then we can flip the tables on their side so we have
|Col. 1|
|a|
|b|
|c|
We do these steps for both columns.
and then we just stitch the two separate tables back into one, using a Combine Tables step.
The final steps give a dummy row number and combine the tables based on that value. So if you had real row IDs or something like that, you could use those as the key value to combining your tables.