SQL and AdventOfCode 2020, on Snowflake

Felipe Hoffa, long-time developer advocate @ Bigquery who recently changed teams to Snowflake, solved most of the AdventOfCode puzzles on Snowflake using SQL. This would typically fall for me in the category of neat-but-not-revolutionary except that there were a few things in his solutions that I truly had been unaware of. Chief among those: the connect by clause! Recursive processing in idiomatic SQL! If you've ever had to parse through a set of hierarchical relationships encoded in a single table with a parent_id, you'll immediately recognize the benefits here.

If you've used connect by in your work, I'd love to hear from you. Any gotchas?