How do I prevent details of my database tables from being viewed in the page source?

I am a beginner.  So, if you reply to this post, please include as much detail as possible.

I have been to several sites that I know are using a database on the backend.  Yet when I look at the source code for the page, I don't see anything the resembles an INSERT, or SELECT statement.  I figured it was designed like this for security.  Now I know that you can't see the ASP code in the page source, but I thought all of the ADO code was inside the script statements and therefore, viewable in the page source code.

I appreciate any advice anyone can give me on this topic.

Thanks, in advance.
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