When a manager tells you (not asks you) to build a data warehouse in Access or Excel; because Microsoft positions both products as part of their business intelligence stack?
When a customer or stakeholder asks you to dump private/closely held data onto a hard drive and mail it to a business partner? (hint: in regulated industries, that's illegal)
When an executive says "we know that it's flawed, but it'll do for now". Notice how the "we" disappears when there is a middle-of-the-night issue and *I'm* the one in the office fixing it.
One can quote "best practices", whitepapers, reference material and law until you are blue in the face. They aren't solutions.
The secret to telling people that someone won't work isn't to have a solution (Excel will never be an appropriate platform for a data warehouse), it's having the respect and confidence of your co-workers and the backing of your management.
If you have neither, there is no solution (you can't fix stupid). Post your resume and go where you will be listened to.
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