X_KEYSET_NULL_KEY

a keyset page holds a null in one of its sort keys

a raw read paged with keyset() orders by a nullable column: a row comparison has no null order, so the null rows fall off every page

keyset({ keys: [{ column: sqlcoalesce(p.published_at, p.created_at), kind: 'timestamptz', direction: 'desc' }, …] }) # or order by a not-null column