how to manage users of web-app

Hi all, I am pretty new to several technologies here. So I am not sure
where to go with my question. I am implementing a web based application
with servlets, JSP, and JDBC. Here is the plan:

1. System will have a user, 'admin,' who can use the web-application's
JSPs, servlets, and JDBC to add and remove members, who are application
users with data maintained on the system.

2. members, through the web app, enter data that is theirs, other members,
execpt maybe admin aren't to change their data.

3. the web app will also offer the general public access (display only) to
membership data by categories. i.e. accross all members, if the member
provided data for the requested category, include the data in the response.

Now here is the question, should I set up a member/password table and manage
the member access through my database or can I/should I use postgres user
accounts somehow? This sounds like a pretty typical need. Is there some
reading I need to do? Where?

Sam Deel
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Everybody's got to believe in something, I believe I'll have another beer...
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