Tricky~22min

The Bus That Never Left the Depot

3 trips are marked completed — meaning the route was reported as run — but every single GPS ping for those trips sits at the exact same depot coordinates. The bus never moved. Twelve other trips also show zero movement, but their status is standby — buses legitimately parked on reserve, not a problem.

Tables you'll query

tripsgps_pings

What you'll learn

Aggregations & GROUP BYJOINsString Functions
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