[PHP] example to give privs on packages instead of give privs directly on table to user to be better DB Security

[Raúl Castro]

In Oracle, a stored procedure executes under the owners identity, not under the 
identity of the caller. Therefore I have knowed that many applications use packages to 
execute insert, update, select, delete statements instead of give user privileges 
directly on table. I'm creating a web application using php and Oracle, but I want to 
use this programing method, I would like to have some example to help me to 
understand, do you have one? This method is suitable on web applications?