EXPLAIN ANALYZE
SELECT u1.uptime_id as uid, u1.uptime_value
  FROM uptime u1
 WHERE u1.uptime_value > (SELECT u2.uptime_value
                          FROM uptime u2
                          WHERE u2.uptime_id = u1.uptime_id+1);

                                                 QUERY PLAN                                                                                 
-------------------------------------------------------------------------------------------------------------
 Seq Scan on uptime u1  (cost=0.00..25022.50 rows=334 width=8) (actual time=0.207..0.614 rows=3 loops=1)
   Filter: (uptime_value > (subplan))
   SubPlan
     ->  Seq Scan on uptime u2  (cost=0.00..25.00 rows=6 width=4) (actual time=0.015..0.026 rows=1 loops=16)
           Filter: (uptime_id = ($0 + 1))
 Total runtime: 0.688 ms