The default photos list (GET /api/v1/photos?per_page=N&sort=taken_at&order=desc)
filters NOT is_trashed AND NOT is_hidden and sorts by
(taken_at DESC NULLS LAST, id DESC). EXPLAIN on the 21k-row table
shows a seq-scan + top-N heapsort (~20ms standalone, multiplied under
concurrent fan-out on page load). The existing single-column
ix_photos_taken_at can't be used because the leading WHERE clause is
two booleans.
Partial index over the sort key, restricted to the visible subset.
Lets the planner index-scan in reverse and stop at LIMIT N.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
1408ec3fa3