Multi-Value compression has increased the table size - response (21) by amit.saxena0782

Hi Dieter,
 
I proposed a MVC to my client for Teradata 12 Tables. As per the analysis, I got around 800 GB approx saving on 2.3 TB of tables giving table level and column level savings. After too much of investigation on MVC, Client has come up with a concern as below:
 
Concern: Some of these columns are derived from bases that can change e.g. pricing strategies, cost price changes, tax (vat).
If any of these bases change the profile of the data in the tables will change, which means that a totally new set of ‘ideal’ compression values would apply.
How often would the compression values be reviewed?
 
As per my understanding , If the column values are more volatile for derived columns then we do not suggest applying the compression
But if columns values are more duplicate and static then apply the compress to save the space.  But on the whole ,  I am still confused that even if the columns are derived, but I somehow still got the savings for that table, around 30%-40 %.
Can you please advise , if there is a way, we can apply compression on tables with some some/all derived columns, as i can see much saving ..
 
Regards,
Amit