Find schema and info of MS SQL Server to which I have access to

Question

I have access to an MS SQL Server DB and I'm able to run queries on the databases.
But the since the database is too big, with multiple tables and each table having many columns (whose names aren't descriptive), I don't know which data is where.

I assumed I could use nc or Wireshark to listen to the port and learn from the backend about data in the DB (I have access to the frontend and the DB). But SQL server data traffic is encrypted. So I downloaded Microsoft Tools like Microsoft SQL server manager and Microsoft Message Analyzer and starting out.

Question
Are there ways to figure out "which data is where" in a DB?
What must be my approach to understand the database?

Answer 1

If I am not mistaken (it's some time since I worked with MS SQL), SQL Server Manager has a feature to reconstruct the database schema, delivering an ER-Diagram, including references between the tables (foreign keys), Stored Procedures etc. This assumes you can connect to the db. Once you have the db schema, this will give you an insight into its structure, and how the tables cooperate.