Re: Add Missing From?

Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Tom Lane wrote:
> >> This description confuses two quite separate issues.
> 
> > Yea, it does.
> 
> > How is this text:
> 
> > * Allow DELETE to handle table aliases for self-joins
> 
> >   There is no way to create a table alias for the deleted table for use
> >   in the DELETE WHERE clause.  The agreed approach is to allow a USING
> >   clause to specify additional tables.  UPDATE already has an optional
> >   FROM clause for this purpose.
> 
> Not a lot better.  They really should be two separate issues, because we
> could in theory do either without the other.
> 
>     * Allow an alias to be provided for the target table in UPDATE/DELETE
> 
>     This is not SQL-spec but many DBMSs allow it.

I don't think we would ever do the above item.  I see no purpose to
allowing the UPDATE/DELETE table to have an alias as long as you can
create another reference to the table that does have an alias.  In fact,
having a alias for the deleted item seems too prone to confusion.

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