Auditing of Oracle Updates

Oracle gurus:

I'm thinking of implementing the Oracle audit process to track updates on 7 tables from basically a data warehouse database. Granted there will be very little audit data generated, but I'm worried about the audit tables filling up because I think(?) they are in the system tablespace. I suppose I could monitor the data and flush out the old stuff. I'm not really concerned about performance issues in auditing of the update process because it occurs so infrequently. ( 1.5 % of the dataset).

Has anyone found the Oracle auditing process to be "better" than say a trigger-type of solution ?

TIA Cliff Buetikofer

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