A site like this probably uses a template structure,
where the layout of the page is stored in a template file that is read by a php script.
The template would contain keywords that are replaced with database content by the php script.
You do not want to write complete pages and store them in a database,
because if you decide to change something in your layout, you'll have to edit all the pages inside your database.
If you use a template, you can change the layhout of your wite by editing just one file.