Change data capture

My apologies in advance if this is an absurd question !!

Can we use MV Logs for capturing change data, just like a log table based on trigger ? I dont want to create MVs though, as the source table is huge ( would reach 250 GB in an 6 months as per our initial estimate, at which it will maintained by periodic purging) and this is already a logical standby for the main application db. What I am thinking is to use the MLOG$ table as a source to extract the changed records every cycle and then delete the extracted records from this log table. Also I dont think I can purge the log, as transactions at that moment will be lost in that case. Not sure if this is a workable idea..

Since the source is a logical standby database , triggers/cdc/streams are not working.

Any suggestions please ?

Thanks in Advance
Bagavath

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