calculate the amount of redo generated by a session

Hello:

If I wanted to calculate the amount of redo generated by a session in oracle 9 database, would that work?

select value from v$mystat where statistic# = 115

update

insert

delete

update

select value from v$mystat where statistic# = 115

Subtract the first value from the second to arrive to the total size of redo generated.
I am basing this on the following:

  1* select * from v$statname where lower(name) like '%arc%' or lower(name) like '%redo%'

        72 redo synch writes
8

        73 redo synch time
8

       114 redo entries
2

       115 redo size
2

Also, if this does look reasonable and assuming that no other sessions are running against this DB,
should the total size of all the archived logs created during the session be close to the difference
between my first and last values?

thank you

Gene Gurevich

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