title: Techniques for understanding complicated legacy database
body: <p>I have inherited a complex, poorly documented SQL Server database and am trying to reverse engineer the tables, their relationships and in general how the data fits together. To do this I am drawing the table diagrams using Visio, attempting to determine the data relationships using the existing queries (there are no relationships actually defined) and using the application logic (what little there is) to help. </p>
  
  <p>This is however quite challenging given the lack of documentation / obfuscated nature of this system and I was wondering if there are any techniques / approaches that can help?</p>