Display Archive Log Generation by Day

SET PAGESIZE 300
SET LINESIZE 300
COL "Generation Date" FORMAT a20

SELECT TRUNC(completion_time)  "Generation Date" ,
   round(SUM(blocks*block_size)/1048576,0) "Total for the Day in MB"
FROM gv$archived_log
GROUP BY TRUNC(completion_time)
ORDER BY TRUNC(completion_time)