-- Для работы скрипта необходим доступ к представлениям
-- V$LOG_HISTORY, V$LOG, V$DATABASE
 

SELECT Start_Date,
 Start_Time,
 Num_Logs,
 ROUND (Num_Logs * (Vl.Bytes / (1024 * 1024)), 2) AS Mbytes,
 Vdb.NAME AS Dbname
 FROM ( SELECT TO_CHAR (Vlh.First_Time, 'YYYY-MM-DD') AS Start_Date,
 TO_CHAR (Vlh.First_Time, 'HH24') || ':00' AS Start_Time,
 COUNT (Vlh.Thread#) Num_Logs
 FROM V$log_History Vlh
 GROUP BY TO_CHAR (Vlh.First_Time, 'YYYY-MM-DD'),
 TO_CHAR (Vlh.First_Time, 'HH24') || ':00') Log_Hist,
 V$log Vl,
 V$database Vdb
 WHERE Vl.Group# = 1
ORDER BY Log_Hist.Start_Date, Log_Hist.Start_Time;