Agree with this as well. Forgot exactly what one was and googled it to make sure. The example that is used here would indicate orphaned records.

http://www.w3schools.com/sql/sql_join_right.asp

There are valid use cases for orphaned records. A quote database might want to allow registered and anonymous submission, for example.

Or, ala Reddit, comments from deleted users.

There's about as much reason to use a right join as there is to use a left join.

Yes, but one of them means that you're thinking about the problem backwards.

I don't think I've ever used a right join in a production query (perhaps a couple of times when I was doing some digging and it was easier), but I don't understand your statement. Left joins are insanely useful. For example, getting all the sales for a salesperson:

    select
        sp.Name,
        sum(s.Amount) as TotalSales
    from
        SalesPerson sp
        left join Sales s on
            sp.SalesPersonKey = s.SalesPersonKey
    group by
        sp.Name
    order by
        TotalSales desc

If you did a correlated subquery, it would take a ton of time to complete (`select sum(Amount) from Sales s where s.SalesPersonKey = sp.SalesPersonKey`), especially on large tables.

Left joins (and full outer joins) are plenty useful and I use them almost daily. Care to explain what you mean?

What he (probably) means is that the following query returns the same result as your query:

    select
        sp.Name,
        sum(s.Amount) as TotalSales
    from
        Sales s
        RIGHT join SalesPerson sp on
            sp.SalesPersonKey = s.SalesPersonKey
    group by
        sp.Name
    order by
        TotalSales desc

EDIT: Formatting.

That's what was meant, I assume, but it's misguided. Right joins don't create a "code smell" for technical reasons, but for practical reasons. Because left joins are the standard approach, if you're using a non-standard approach to a common problem you'd better have a damned good reason (because you're just confusing maintenance programmers... and thus causing errors... with no justification, otherwise).

Ditto.