Index corruption after unclean shutdown
Postgres 13. A query that filters on `email` started returning *no rows* for users that definitely exist (an index-only lookup), while a seq-scan of the same table finds them. This began after the host had an unclean shutdown last week from a kernel panic; the DB came back up and ran fine until now. `amcheck`'s `bt_index_check` on the `email` btree throws errors. The cluster is a primary with one streaming replica. Triage, restore correctness now, and figure out blast radius.
What a strong answer looks like
Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.
0:00 of about 40 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.