Comment by drittich

I don't think it's falling apart at all. Personally, I would require that what columns get returned be explicit (optionally with a * type syntax that you have to enable - the defaults should be safe and * has its risks). For one thing, you don't necessarily want to return all the columns you have aggregated. E.g., you may be running the equivalent of a HAVING clause on an aggregate column, so don't need the value returned.

"Each line transforms the previous result." - I assume this is referring to the order that transpilation happens, so you can read it top to bottom and understand the flow easily.

One thing I would like to see is how a recursive CTE might look.