Whats wrong with this query???

select shift, record_date, sum(timelost)
from
(select shift, substring(rcd_timestamp,1,8) record_date, timelost
from my_table)
group by shift,record_date

-------------------------------------------------------------------------------------
shift timelost rcd_timestamp
B 2.2106481481481482E-3 20060123234610
B 0.2106481481481482E-5 20060123232353
B 1.2106481481481482E-1 20060124231278
A 3.2106481481481482E-3 20060125233452
A 4.2106481481481482E-3 20060125233241

sorry..i got it...i was missing the table name....!