create a portal with php and joomla

I am new in php and joomla and for now, studying book "Sams Teach Yourself PHP in 24 hour".

I want to create an portal with PHP (and Joomla) that certain people with definite level of access can input data or use data...

Please tell me how should I do开发者_JAVA技巧 this? I must start from what and where?

Is reading PHP and be familiar with Joomla is enough?

Thanks in Advance...

Knowing PHP should be enough, and i don't know Joomla in detail, but i think only Joomla also might do the trick alone, and if so this might be way less work to do, depending on how exactly you want your portal to be.

I don't think You need to study php. You better learn more about Joomla. There are many options to set priviledges and stuff.

Joomla allows different access levels, but you must decide whether they fit your users' needs yourself. I would advise checking this out prior to starting the project: http://help.joomla.org/content/view/228/153/1/1/

You can run and extend a Joomla site with no knowledge of PHP at all. Since your question isn't specific it is hard to give an exact answer, but I can point you in the right direction. Since you need access control levels, you definitely want to use Joomla 1.6. It has very good ACL that you can use to control every part of the site.

As for as a "portal" that really depends on your needs. Joomla has built in user registration as well as user submitted content, but it is rather limited in scope. If you are looking for a full blown community portal then you should take a look at JomSocial (will be 1.6 ready soon). More details on what your portal needs would be helpful though.