If it were only a restriction, the restriction might only apply to people without enough credentials. Indeed, there are such restrictions, and there are people who have permissions (using the web interface) to see things that others cannot see, due to these restrictions. However, the web interface also has limitations, things it simply has not been programmed to do, irrespective of the permission bits attached to your account; these limitations can nevertheless be bypassed by the few people with direct access to the database.
So the web interface has both limitations and restrictions.
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