{"criteria": {"c1": "not_met", "c2": "not_met", "c3": "not_met", "c4": "not_met", "c5": "not_met", "c6": "not_met"}, "note": "Proposes created_at range sharding for every table and claims all four queries hit one recent shard (wrong for timelines, likes on old posts, follower counts); search uses LIKE rather than a search index; no tradeoffs (e.g. time-range hot shard) are named."}