Re: special join

Nikolaj Lazic <[email protected]> Mon, 7 Sep 2020 11:52:21 -0000 (UTC)
Newsgroups comp.databases.mysql
Organization CARNet, Croatia
Message-ID <[email protected]>
Dana Mon, 7 Sep 2020 12:26:14 +0200, Jan Novak <[email protected]> napis'o:
> Hi,
>
> i have a table "server" with auto_increment field ID and a table "ip", 
> with a filed "SERVER_ID" corrosponding to "server.ID"
>
> select ip.VALUE as "ip" from server, ip where server.DELETED=0 and 
> server.ID=ip.SERVER_ID
>
> If in "ip" table for the server are more then one ip adress are saved, i 
> get in my results the server also more then one time listed.
>
> My question is: how can i get only the server with the first IP from the 
> ip Table, if more then one ip's saved there.

group by... count... and then select those >1.

https://www.w3resource.com/sql/aggregate-functions/count-with-group-by.php