Re: [SQL] Select Query Help

According to Shawn T. Walker:
>
> Hello All,
>
> I am designing a database for a ISP call center. This is the
> Select statment that I am trying to use to allow a employee search for
> a user. It displays all of the information that I would like it to,
> but if any of the items in the where clause are not found then that
> item will not come up on the screen. Can anyone give me any
> suggestions?
>
> Thanks in advance.... The mailing list has been great!!!! :)
>
> select myob.username,myob.lname,myob.fname,radius.ip_username,account_types.account_title,status.status_name
> from myob,radius,account_types,status
> where myob.username = radius.username AND radius.account_type = account_types.account_type AND radius.status = status.status
> order by username;

That's just the way SQL joins are supposed to work. If you want to
also display non-matching elements in the same query you have to
UNION with another select that gets them. In general, though, it
is a bad idea to allow the tables to get out of sync with respect
to records containing the key fields. Unfortunately PostgreSQL doen't
have a way to enforce this internally so it is up to the client app.

Les Mikesell
les(at)mcs(dot)com