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Sessions generating more redo or SQL queries generate heavy archive logs

Many times customer would ask us  that why more number of archive logs are being generated & flash recovery area (FRA) is getting filled with archive logs?  What are the queries or sessions involved in generating more archive logs?

below we can see the sql query to find which sessions and sql statements are generating more redo or more number of archive logs....

current sessions generating redo
=================================
set lines 2000
set pages 1000
col sid for 99999
col name for a09
col username for a14
col PROGRAM for a21
col MODULE for a25
select s.sid,sn.SERIAL#,n.name, round(value/1024/1024,2) redo_mb, sn.username,sn.status,substr (sn.program,1,21) "program", sn.type, sn.module,sn.sql_id
from v$sesstat s join v$statname n on n.statistic# = s.statistic#
join v$session sn on sn.sid = s.sid where n.name like 'redo size' and s.value!=0 order by
redo_mb desc;

From the above query we can have the session and sql id which generates redo currently in a descending order.

Output:
current sessions generating redo









The above method is for current situation.

Sometimes customer would ask the sql query which generated more archive logs sometimes before or days before (not for current archive logs generation which is explained in this post).  We'll see the steps for this scenario in the next post...

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