feedback form save to database example code to learn?

Is there example php or perl code that allows the input/capture of (for
example) name, email address, comment, ip address of submitter, date, for a
website?

I'd like a simple example of how the connection is made between a plain html
web page that would contain the additional fields above, whatever php/perl
file is used to house the username/password that opens the database, where
that file is kept, how it is prevented from being viewed by someone for
example attempting to mirror or spider the site, how the data is transferred,
and how the connection is closed.

I don't need a step-by-step, a working example of a feedback page setup that I
can implement into a production web site would help because I'll simply look
at the code and figure out how it works.

I have 3 books, one on php5 & MySQL E-Commerce, one PHP & PostgreSQL advanced
web programming, and Beginning Databases with PostgreSQL, but I'm getting
caught on the simplest of things I think.

The server is Debian Sarge/Stable, with the Debian Stable version of
Postgresql (7.4.7-6Sarge) Upgrading to 8.x isn't an option, I'm sticking to
Debian's stable version.

I think the above example (feedback page) is the easiest for me to understand
and be able to implement in a working setup. The feedback once received
should simply be saved in a table, without having to be forwarded via email
or on the server to anyone else.

tia,
Bing.

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