I recently had to sort out a database for a client. It was a mess….
The database was for people to contact, sort of like a telemarketing system (their choice, not mine…). The problem that they were having was that the database contained a lot of entries that had people with different names at the same address with the same phone number. As you can imagine, calling the same people over and over again just because their phone number has come up again was not the best way to make friends.