I have a quick question about how to query this information
So let's say in my database I have topics of
Welcome Center Group 1
Members Questions Group 2
Admin Ops Group 3
and a users table of
User 1 Group 1
User 2 Group 2
User 3 Group 3
and a group tables of
1 Register User
2 Member
3 Admin
Okay so that would be something like a database, now say I only want register a user with a group 1 to see Items with group 1.
"SELECT * FROM topic WHERE group = 1"
So they can't see the stuff for the member's and admin's.
This is where the problem starts.
I need to find a query where, or learn away that we allow the member to see the registered users topic and the members topic.
"SELECT * FROM topic WHERE group = 1 AND group = 2"
As you can see this an example and not sure if this is what I need to do.
Same with Admins, I need them to be able to see the registered user topics, member topics, and the admin topics. So all three.
"SELECT * FROM topic WHERE group = 1 AND group = 2 AND group = 3"
As you can see that I am not one hundred percent sure that this will work, before I waste my time coding something that isn't going to be like this but the query is where I am kinda stuck at.
If you want all topics that have both groups, then use aggregation and a having
clause:
SELECT t.topic
FROM topic t
GROUP BY t.topic
HAVING SUM(group = 1) > 0 AND
SUM(group = 2) > 0;
Note that group
is a bad name for a column because it is a reserved word.
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