The simplest of all possible SQL bundles....

• Edit the environment variables in the preferences to the values for your database ("Bundles" -> "Show Bundle Editor...", then select "MySQL prefs" under the "MySQL" bundle).

• Then open a file (your "worksheet"), type a SQL query, select it, and do "MySQL execute" (or Ctrl-Cmd-Return).

• The query results are written back to the same worksheet. That's basically it.

SQL language file stolen from the SQL bundle.

Update 2011/1/14: Now with a new clever feature/cheesy hack! If you name your worksheet file something like "worksheet..sql", then queries will automatically go to that database -- so you can keep separate worksheets for different databases.