Understanding Table design in database I have 3 years of SQL Server development work experience. Now I am moving to a new company (first jump). I heard in my new company they deal with too many tables. 

What is the best way to understand table design in a database? How do you SQL gurus analyse the table design when you move to a new company?

Is ER diagram the best way? Please share your experience on this.
The database is an encoding of the business rules. Without understanding the rules there is no way of making sense of the database. Take it piece-by-piece, focusing on one area until you have a reasonable understanding of it.

Even if documentation exists I like to draw ER diagrams from scratch as it helps me remember the connections. It also allows me to compare how I would have done it to how it is currently implemented. The differences are an opportunity for further learning.

Reading the code will bring out further "virtual" FKs and alternate keys that are not declared explicitly.