Add the capability to provide informational relationships, constraints and hints that would help building a data model within Databricks itself. I understand this is a Spark feature which is pending since 2017 to provide Informational Referential integrity [SPARK-19842] but it hasn't moved on.If Databricks can provide a similar feature at least with Delta then there is no need of using an intermediary model-staging service like a RDBMS or OLAP or MPP when visualizing using tools like PowerBI or Tableau.