There's an open-source tool called SchemaSpy that I have found to be very useful. It can create an entire interactive website for the schema.
It's a
Java application using
JDBC, so you can do things like run the app on a Windows machine and analyze an AS/400 or even z/OS database as long as you have JDBC drivers.
I think you can find SchemaSpy on sourceforge.net. If not, Google.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.