Daily SQL and Python Challenges for Data Engineers
Daily Data Engineering Challenge - 2026-11-12
A fresh SQL and Python challenge every day. Practice data engineering skills with adaptive difficulty that matches your level. Track your accuracy, build streaks, and find your weak spots.
Today's SQL Challenge: Radio Silence
An engineering manager is auditing which repositories have gone quiet, where a repository's longest silence is the widest stretch of days between two back-to-back commits. Commit timestamps are stored as text and the queries run on SQLite, so the day count has to come out of the stored timestamps. Limit the audit to repositories with a long track record, more than 31 stretches between consecutive commits, and for each surface its longest silence from most silent down, numbering the standings as you go.
Today's Python Challenge: The Shortest Route
A message-routing service keeps an adjacency dict mapping each node to the nodes it can forward to directly. Given that `graph` and 2 node names, return the fewest hops from `start` to `end`, or -1 when `end` can't be reached.