Read these troubleshooting tips before using the DDL import option to generate data models in Vertabelo. Avoid running into potential errors that waste your valuable designing time. Few data modeling tasks start from a blank sheet of paper. More often, we work on a pre-existing database. You don't want to draw an ERD of an existing database from scratch. But I don’t have to tell you that. This task is much simpler and infinitely faster with a modeling tool that can load the database structure using a DDL import feature.