-- Remap detection (ยง6.9) and unstable-id servers: without these indexes -- each upsert in a 500-row batch can scan the whole track table. CREATE INDEX IF NOT EXISTS idx_track_remap_path ON track(server_id, server_path) WHERE deleted = 0 AND server_path IS NOT NULL AND server_path != ''; CREATE INDEX IF NOT EXISTS idx_track_remap_hash ON track(server_id, content_hash) WHERE deleted = 0 AND content_hash IS NOT NULL AND content_hash != '';