On Sun, Sep 16, 2012 at 11:58:06PM -0400, Tom Lane wrote:
> barrybrown@sierracollege.edu writes:
> > I sometime see my users delete all rows from a table using a command like
> > this:
>
> > DELETE FROM customer *;
>
> > The question is: what is the star? Is it a table alias or an
> > output_expression?
>
> Neither; it specifies to search the table and its inheritance children,
> ie, the opposite of ONLY. This has been the default behavior (unless
> you change the setting of sql_inheritance) for many years, so "*" has
> largely fallen into disuse; but it's still accepted.
>
> However ... I went looking for documentation on this point, and I'm
> darned if I can find any. There certainly used to be some, but
> apparently somebody got over-eager about editing the docs to reflect
> the modern default behavior. The "*" doesn't even appear in the syntax
> summaries for most of the commands where it's allowed, which is flat
> wrong --- anywhere you can write "ONLY tablename", it's valid to write
> "tablename*" instead.
>
> So we have some docs work to do. Thanks for pointing it out.
Is there any value to having * vs just not using ONLY? I am not sure
documenting this is helping us, and it would add more clutter. Isn't
this like how we don't document the old COPY syntax.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ It's impossible for everything to be true. +