Robert Haas <robertmhaas@gmail.com> wrote:
> Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Personally my advice is to avoid USING: it wasn't one of the SQL
>> committee's better ideas.
>
> I don't understand why we can't just translate the USING into some
> equivalent construct that doesn't involve USING. I proposed that
> a while ago and you shot it down, but I didn't find the reasoning
> very compelling.
There's no query you can write with USING that you can't write in a
longer form with ON; but a query of moderate complexity can become
significantly shorter with USING, and thus easier to understand and
less prone to bugs than the ON form. I think it's a mistake to
discourage USING or under-support it compared to the more verbose
constructs.
-Kevin
