portal=# explain analyze SELECT t1.detectorid, description, t1.total as count, t3.count,
       CAST(t1.total AS NUMERIC) / CAST(t3.count AS NUMERIC) * 100.0 AS percentage
FROM selena.test_agg t1,
      selena.detectorid_count t3
WHERE t1.detectorid = t3.detectorid
ORDER BY t1.detectorid, description, t3.count;
                                                            QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=145.30..148.77 rows=1386 width=19) (actual time=6.407..7.116 rows=1386 loops=1)
   Sort Key: t1.detectorid, t1.description, t3.count
   Sort Method:  quicksort  Memory: 157kB
   ->  Hash Join  (cost=17.20..72.97 rows=1386 width=19) (actual time=0.972..5.238 rows=1386 loops=1)
         Hash Cond: (t1.detectorid = t3.detectorid)
         ->  Seq Scan on test_agg t1  (cost=0.00..22.86 rows=1386 width=15) (actual time=0.028..0.909 rows=1386 loops=1)
         ->  Hash  (cost=9.31..9.31 rows=631 width=8) (actual time=0.920..0.920 rows=631 loops=1)
               ->  Seq Scan on detectorid_count t3  (cost=0.00..9.31 rows=631 width=8) (actual time=0.028..0.469 rows=631 loops=1)
 Total runtime: 7.880 ms
(9 rows)