SaaS engineering teams evaluating safe Postgres tuning
Research question
When a buyer shows a slow Postgres query, what minimum evidence should exist before QueryRook recommends an index? The working answer is a proof packet, not a naked CREATE INDEX statement.
Method
Group the workload by normalized fingerprint, inspect the current plan, propose the smallest plausible candidate index, test the hypothetical plan, and record the caveat that would block automatic promotion.
Operator use
This note becomes a checklist for the product: every index recommendation should show the fingerprint, current plan, shadow plan, expected benefit, lock posture, and rollback story in one reviewable packet.