We had an issue where a query to a db replica set was returning duplicates randomly when paging. Aka each HTTP call for next N results was hitting different dbs with same/copy data.

No one could figure out why... I look at the query and ask where's the ORDER BY ID?

These guys were interviewing ppl last week and saying how even they could solve algo questions they were asking candidates.

And so to explain the problem, I'm like "tell me what's the difference between a list and a sorted list?"

#why algo questions suck at predicting job performance