Ted Dziuba in his effervescent tone:
There are a couple of really common Single Point of Truth Rule violations I’ve seen in the web world, and they almost all revolve around misconceptions about databases. No, wait, strike that. Almost every SPOT violation I’ve seen stems, in one way or another, from MySQL’s failure at being a database. Actually, most of the NoSQL catastrophe is a product of MySQL’s perverse representation of the SQL spec, but that’s not the drum I’m here to beat.
All his examples are contradicted by real life scenarios though.
Original title and link: The Single Point of Truth Rule: The Most Important Concept in Systems Design ( ©myNoSQL)