Hello Wander E.
I am really sorry for the delay of this reply as it is a weekend for us here.
Yes, you wouldn't need to manage it from your database table, you can configure from your backend > Easydiscuss > setting > categories > select the categories > Click "Permission" tab >
Add the public user group/ guest user group in this section "who can view this discussion in this category", see my screenshot (
http://screencast.com/t/Ahr3nQnaZQh )
Please let us know if you need further assistance and provide us with your Joomla backend access so we can help you check on this? Please advise.