running postgresql on a private machine accessing it from public web pages

We have a private machine that runs postgresql and have created a
database. We want to access that database from the web for plotting
using php. The web server and pages are on a public (different) machine
that does not have postgresql. Nor will they install it for is. The
postgresql database is also on the public machine (which the private
machine can access).

So, the question is, can someone go through these (public) web pages and
access the postgresql database if the postgresql server is running on
the private machine?

We have other data in the postgresql and would like to only have to use
one database types, i.e., postgresql.

Thanx,
keith

--
"Nonviolence is not a cover for cowardice, but it is the supreme virtue of the brave."  Mohandas Karamchand Gandhi
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Keith D. Evans
Joint Center for Earth Systems Technology/UMBC
(301) 614-6282 (M,Tu)
(410) 455-5751 (W,Th,F)
http://www.jcet.umbc.edu/bios/evanmain.html
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Any opinions expressed in this email are not those of
NASA, or the Goddard Space Flight Center, or the Joint
Center for Earth Systems Technology or the University
of Maryland Baltimore County.

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