A good way to quickly survey the information in a database is to apply a tool that automatically creates a database diagram of all tables and all relationships between them.
In my experience, such tools use foreign keys as the relationships, which most of the databases I try them do not contain. Sure, they satisfy constraints corresponding to foreign keys, but do not enforce them. And I'll end up with a 'diagram' consisting of a bunch of unrelated tables.
So what I'm looking for is software that can compute "undeclared foreign keys" and either
Do you know any tools, free if possible, that can already do this?
The following products are all claiming to provide foreign-keys discovery abilities:
Statistical methodologies able to provide a kind of similarity rank like range distribution and creation time as suggested by Kirk, seems to be the right way. .. I'd need to implement it using SAS EG or any free tool.