Database crimes
The 40-year-old database crime every bank (and most companies) still commit in 2025
I’ve worked with banking systems for 35 years.
Every single one of them, without exception, still stores contact details like it’s 1985:
1 field for Phone
1 field for Mobile
1 field for Fax (yes, really)
1 field for E-mail
Result?
Receptionists have 27 Post-it notes around their screen.
Sales keeps an Excel with the real mobile numbers.
Customer service can’t see the private e-mail the client actually uses.
And yes, companies still have a fax number in 2025.
This is not a business problem.
This is a database design crime that costs companies money in lost productivity.
The fix? 5 minutes of thinking + 1 extra table.
Correct structure.
Table: Contact_Info
ClientNr (your normal customer ID)
ContactPerson (John Doe, Emergency contact, etc.)
ContactType (Work phone, Private mobile, WhatsApp, Signal, Support hotline…)
IsPrimary (yes/no)
Notes (Only after 17:00, Prefers Signal)
ValidFrom / ValidTo
You get the point. That’s it.
Suddenly:
A customer can have 20 numbers and you always call the right one
When someone changes job → just set ValidTo = today (no deleting)
Reception sees Call private mobile after 18:00
Compliance loves the audit trail
Post-it notes finally die
I tried to implement this exact pattern in the bank I worked for.
Guess what IT said?
Too much work (really), it works fine now.
Except it didn’t.
Half the screens were invisible behind Post-it notes.
And every sales person had a private excel sheet for contact information
You do not want to know what happened when that file got corrupted.
The real problem?
The real problem?
Nobody ever asked the people who actually use the system.
Ok, I asked. And that is it. I asked, had a solution, and nothing happened.
Tell me in the comments: how many phone numbers does your CRM currently allow? 😅
This brings us to the end of my post on Database Crimes?
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Disclaimer
All tips and methods mentioned in this blog are tested on Windows 11. Please note that results may vary on other operating systems or versions of Windows. Adapt the instructions accordingly.
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