SQL Query to delete select users

[Snowhog]

We, as most vBulletin Forums, end up with new members who never return and have never posted. I call them 'drive-by registrants'. I already have an SQL Query I use to identify them:

select username, posts, usergroupid, from_unixtime(joindate), from_unixtime(lastvisit) from user where lastvisit = joindate and lastvisit < (unix_timestamp() - (86400 * 730)) and posts = 0 and usergroupid = 2 order by from_unixtime(lastvisit);

I change the value in (unix_timestamp() - (86400 * 730)) to reflect 'number of years', so:

1=365 2=730 3=1095 4=1460 5=1825 6=2190 7=2555 8=2920 9=3285 10=3650

Currently, using 730 (2 years), there are 100 such members. Using higher values, there are none.

I want to utilize an SQL Query to delete these users and have written this:

delete from user where lastvisit = joindate and lastvisit < (unix_timestamp() - (86400 * 730)) and posts = 0 and usergroupid = 2;

As this is a permanent action, I'd like a qualified review of what I've written, letting me know if it's okay.

[glennrocksvb]

It's safer to delete using the AdminCP. There are other tables to update other than the user table.

[Snowhog]

Yeah, but using AdminCP > Users > Prune / Move only allows for 'Has not logged on for x days' (equates to 'Last Activity'). So setting the search to:

Usergroup: Registered User
Has not logged on for x days: 730
Join Date is Before: Todays date
Posts is less than: 1
Order By: User Name

235 users are identified, 135 more than my SQL Query identifies.

What I'm trying to avoid is having to manually review the Prune / Move results against my SQL Query results.

[glennrocksvb]

where lastvisit = joindate

That's where the difference is in your query. You're only looking for users who have joined and last visited on that day they joined. How about those users who logged in the succeeding days but still never posted?

[Snowhog]

How about those users who logged in the succeeding days but still never posted?

Yes, there are those; lot's of those. But, there are a lot within those who are active; they login but haven't posted. I'm okay with those, if the lastvisit date is 'recent' as compared to their joindate. Nobody's required to post to our forum, and many don't but do login when visiting. It's those who once registered never login again that I want to remove.

[Snowhog]

I created a new Usergroup called DriveBys (usergroupid = 67)

I can use the following SQL to accomplish what I want.

update user set usergroup = 67 where lastvisit = joindate and lastvisit < (unix_timestamp() - (86400 * 730)) and posts = 0 and usergroupid = 2;

Afterwards, I can delete these users via AdminCP > Users > Prune / Move, specifying Usergroup DriveBys.

Do you see any issues with this process?