Comments on database page:
The way people read a page, I would break the following text out from the grey box its in because its not logically related, it really goes with the next chunk:
[service0@yourserver sql]$ cd postgresql/
[service0@yourserver postgresql]$ emacs samplenote-create.sql
either put it in its own gray box, add it to the next one or do it in the whitespace between ..
Just a nit :)
Nice work!