Structure of a Comment System - sql

Question

I want to manage a n-label comment system and design a data base structure like this.
I am trying to design a database which supports comment moderation for unregistered users. The functionality I require is such that when a comment is posted
If the user is registered it appears directly. otherwise;
The post must be checked by a moderator before it appears.
Please suggest the possible changes to my database schema above to support this functionality.

Answer 1

It appears that you have more-or-less what you require in order to do what you want. The process when a user creates a new comment is as follows
if the user is registered, and not blocked
create BlogComment record with:
IsApproved=true
IsBlocked=false
UserId=registered userId
UserName = null
if the user is registered and blocked
create BlogComment record with
IsApproved=false
IsBlocked=true
UserId=registered userId
UserName = null
if the user is unregistered
create BlogComment record with
IsApproved=false
IsBlocked=false
UserId=null
UserName=user's name
When you pull out comments to show below a post you want a query like
SELECT Comment, ISNULL(bc.UserName, ru.UserName) AS UserName
FROM BlogComment bc
LEFT JOIN RegisteredUser ru
ON bc.UserId = ru.Id
WHERE postId=<current PostId>
AND IsApproved=1
This will pull out all approved comments (those from registered users, or from unregistered users which have been moderated), along with their username (for registered users this will be their username from the RegisteredUser table, for unregistered it will be what is saved alongside their comment in the BlogComment table)
Lastly, when you want to pull out a list of posts for the moderator to moderate
SELECT *
FROM BlogComment
WHERE IsApproved=0
AND IsBlocked=0
You can then update the records they accept to IsApproved=1.