2:13 guest@softwareheritage => explain analyze with closest_two_visits as ((
    select ov, (date - '2021-05-03 10:00:00+00'), visit as interval
    from origin_visit ov
    where ov.origin = 2695882
          and ov.date >= '2021-05-03 10:00:00+00'
    order by ov.date asc, ov.visit desc
    limit 1
  ) union (
    select ov, ('2021-05-03 10:00:00+00' - date), visit as interval
    from origin_visit ov
    where ov.origin = 2695882
          and ov.date < '2021-05-03 10:00:00+00'
    order by ov.date desc, ov.visit desc
    limit 1
  )) select (ov).* from closest_two_visits order by interval, visit limit 1;
                                                                                             QUERY PLAN                                                                                             
────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 Limit  (cost=4134.89..4134.89 rows=1 width=64) (actual time=338.578..338.586 rows=1 loops=1)
   ->  Sort  (cost=4134.89..4134.90 rows=2 width=64) (actual time=338.576..338.584 rows=1 loops=1)
         Sort Key: closest_two_visits."interval", ((closest_two_visits.ov).visit)
         Sort Method: quicksort  Memory: 25kB
         ->  Subquery Scan on closest_two_visits  (cost=4134.84..4134.88 rows=2 width=64) (actual time=338.553..338.568 rows=2 loops=1)
               ->  Unique  (cost=4134.84..4134.86 rows=2 width=56) (actual time=338.545..338.557 rows=2 loops=1)
                     ->  Sort  (cost=4134.84..4134.85 rows=2 width=56) (actual time=338.543..338.549 rows=2 loops=1)
                           Sort Key: "*SELECT* 1".ov, "*SELECT* 1"."?column?", "*SELECT* 1"."interval"
                           Sort Method: quicksort  Memory: 25kB
                           ->  Append  (cost=2064.12..4134.83 rows=2 width=56) (actual time=336.115..338.440 rows=2 loops=1)
                                 ->  Subquery Scan on "*SELECT* 1"  (cost=2064.12..2064.13 rows=1 width=76) (actual time=336.113..336.119 rows=1 loops=1)
                                       ->  Limit  (cost=2064.12..2064.12 rows=1 width=84) (actual time=336.101..336.105 rows=1 loops=1)
                                             ->  Sort  (cost=2064.12..2064.37 rows=103 width=84) (actual time=336.099..336.101 rows=1 loops=1)
                                                   Sort Key: ov.date, ov.visit DESC
                                                   Sort Method: top-N heapsort  Memory: 25kB
                                                   ->  Index Scan using origin_visit_pkey on origin_visit ov  (cost=0.58..2063.60 rows=103 width=84) (actual time=30.165..334.786 rows=562 loops=1)
                                                         Index Cond: (origin = 2695882)
                                                         Filter: (date >= '2021-05-03 10:00:00+00'::timestamp with time zone)
                                                         Rows Removed by Filter: 50
                                 ->  Subquery Scan on "*SELECT* 2"  (cost=2070.68..2070.69 rows=1 width=76) (actual time=2.311..2.314 rows=1 loops=1)
                                       ->  Limit  (cost=2070.68..2070.68 rows=1 width=84) (actual time=2.296..2.298 rows=1 loops=1)
                                             ->  Sort  (cost=2070.68..2073.12 rows=978 width=84) (actual time=2.294..2.295 rows=1 loops=1)
                                                   Sort Key: ov_1.date DESC, ov_1.visit DESC
                                                   Sort Method: top-N heapsort  Memory: 25kB
                                                   ->  Index Scan using origin_visit_pkey on origin_visit ov_1  (cost=0.58..2065.79 rows=978 width=84) (actual time=0.083..2.210 rows=50 loops=1)
                                                         Index Cond: (origin = 2695882)
                                                         Filter: (date < '2021-05-03 10:00:00+00'::timestamp with time zone)
                                                         Rows Removed by Filter: 562
 Planning Time: 0.576 ms
 Execution Time: 339.250 ms
(30 lignes)