[cjc]

This is great, but if you use OS X and need a more powerful solution, I would recommend http://www.malcolmhardie.com/sqleditor/.

I keep the DB schema of my current project open at all times. When I change something in the database, I immediately make the change in SQLEditor (and vice versa). This is a recent change in my workflow, but so far it has reduced errors when moving from our development to live environments and reduced the time needed to look up obscure fields or relationships.