时间相加 ，使用SQL完成

with a as(select 3.254 times from dual union all
          select 2.546 from dual union all
          select 0.24  from dual union all
          select 12.35 from dual   )

select sum(trunc(times)) +
       trunc((sum(trunc(mod(times, 1) * 100)) +
             trunc(sum(mod(times, 0.01) * 1000) / 10)) / 60) ||':'||
       mod((sum(trunc(mod(times, 1) * 100)) +
             trunc(sum(mod(times, 0.01) * 1000) / 10)) , 60)||':'||
       mod(sum(mod(times, 0.01) * 1000) , 10 )
  from a;

-- 3.254 代表 3分钟 25秒 800毫秒