Long Term Backups and Retrieval strategies

With different legislative and customer requirements, we are troubled by the fact that we may have to make data backups available for 7 to 15 years {some requirements are as long as 15 years}.
The usual restrictions about the same hardware and operating systems not being available 10 years later come to mind first.

How have other organisations devised backup strategies for such requirements ? Are your business users and applications teams able to identify specific data sets
{rows/tables/reports} that need to be backed-up or are you just told to "backup the whole database"
for 15 years ? What backup media do you use ?

Hemant

Hemant K Chitale
http://web.singnet.com.sg/~hkchital

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