Any emacs packages available for browsing databases (viewing schemas, running sql queries)?

I'm giving emacs a try for the first time and I was wondering if anyone has recommended strategy for connecting to databases (I regularly work with mysql, oracle, 开发者_JS百科and sqlserver). I'm looking for a solution that would provide similar functionality to what phpmyadmin provides for mysql but available from within emacs.

Yes, a bunch of links on emacswiki.