There aren't any free or Open Source tools available that are any good, AFAIK.  There's a schema browser tool for Oracle that's Open Source and uses Gtk and it looks really nice, but it doesn't do any of the fancy stuff you're talking about.

If there *are* any good Open Source tools it would be great to hear about them.

The OpenACS Scheme Browser (which works under Oracle with my repaired ora8.c which I've not gotten around to making available yet) at least lets you find out which tables have foreign keys pointing to your table, triggers on your table, etc.  Not much but it does help some...

The problem with the data modeling tools is that the common ones -- ERwin, PowerDesigner, ER/Studio -- are all expensive ($3,000 or so) and surprisingly mediocre. I spend a lot of time in ERwin (and I used to teach PowerDesigner as a certified Sybase instructor), and it's just amazing how many bugs, unintended "features", and missing features are in them. (Not a one of them can do a decent job doing an automatic layout of a reverse-engineered database, even though reverse-engineering was one of the top uses of the tool in every PowerDesigner class I taught.) I suppose we could do one of the "web publish" deals, but I don't know if that's really helpful.

I'm downloading theKompany's DataArchitect now to try it out, although I admit that my expectations are not high when it's selling for 1/100 of the competition's price. And I wonder how long before Sybase's lawyers give the Kompany guys a call about using "DataArchitect" as a name, since Sybase has called the ER-modeling piece of PowerDesigner "DataArchitect" for a long time. (Even back when it was called "S-Designor".)

You'll notice that there's no claim that it's production software at this point ...

I must be suffering from an inability to comprehend the written word.  Here is the quote from the product page that led me to believe that they're telling you upfront that it isn't quite ready for prime time.  I've emphasized some things that triggered my opinion so you can tell me why I'm wrong:
<blockquote><i>
Data Architect <font size=+1><b>will</b></font> be available for Linux and Windows platforms.
</i></blockquote>
Here's a statement from their Changelog page which makes it clear they're concentrating on PostgreSQL and even there have a ways to go:
<blockquote><i>
The plan was to get 100% of PostgreSQL support done for this release but the Linux World show in San Francisco caused that to be pushed back. However, this release does contain much better PostgreSQL support and better ODBC support.
</i></blockquote>
OK, the release in question was at the end of August but this certainly makes me feel that they're being upfront about the fact that the product's a preliminary version.
<p>So, sure, it breaks now (so does OpenACS 4.x alpha in many horrible ways) but that's why it's not done by anyone's standards - including theirs.

people using oracle should check out http://tora.sf.net

its gpl and uses the qt toolkit and works for nix and win platforms.

ObjectsbyDesign.com has an interesting list of UML tools. Not sure which one I would use for OACS,

We are introducing a new exciting, state of the art, Oracle modeling product. Check the free version at www.modelright.com.

try SQLPOWER tool, power*Architect
is open source.......

you'll like it.....