How to decide when is use ERD or UML for data modeling? A UML diagram can be used both to model database designs and class designs, but an ER diagram should be used exclusively in database problems. How do you pick one graphical representation over the other?
I think you answered your own question. E-R diagrams are meant to be problem solving diagrams for the sake of creating a database schema, whereas UML are supposed to model a completed db. I personally don't place a huge amount of value on ER diagrams, as I would personally do such brainstorming in my head, but I imagine many people would swear by them. As such, the answer is UML as a general rule, but ER can hypothetically be useful in the construction of databases.