text: select pg_sleep(2);
  
  insert into cmpTS values(1,current_timestamp);
  drop table tx;
  insert into cmpTS values(2,current_timestamp);
  
  select true 
  from cmpTS a, cmpTS b 
  where a.c1 = 1 and b.c1 = 2 and (b.ts-a.ts)>'00:00:02';
  
  select a.ts as ts1,b.ts as ts2 
  from cmpTS a, cmpTS b 
  where a.c1 = 1 and b.c1 = 2 and (b.ts-a.ts)>'00:00:02';
  