Thread: FROM clause omitted

I had a bug in one of my queries that wasn't detected by pg because if 
filled in the from clause by itself. Take for example a querie like

select foo.a;

which I guess is transformed to

select foo.a
from foo;

Is this really a good thing to do? Is it part of the standard? Can it be
turned of? In my case it hid a bug and made my query work but produce the
wrong result.

Isn't this yet another case of "helpful" parsing that will only hurt in
the end? Look at how hard it is to parse html-pages because all browsers
accept broken code, but different broken code.

What about an example like this (the transformed code above but with alias
x added):

select foo.a
from foo x;

By adding the alias x the query still workes but gives a different result.

-- 
/Dennis

> Is this really a good thing to do? Is it part of the standard? Can it be
> turned of? In my case it hid a bug and made my query work but produce the
> wrong result.

7.4 has a switch to turn this off for the same reasons you cite.

>
> I had a bug in one of my queries that wasn't detected by pg because if

> filled in the from clause by itself. Take for example a querie like
>
> select foo.a;
>
> which I guess is transformed to
>
> select foo.a
> from foo;
>
> Is this really a good thing to do? Is it part of the standard? Can it
be
> turned of? In my case it hid a bug and made my query work but produce
the
> wrong result.
>
> Isn't this yet another case of "helpful" parsing that will only hurt
in
> the end? Look at how hard it is to parse html-pages because all
browsers
> accept broken code, but different broken code.
>
> What about an example like this (the transformed code above but with
alias
> x added):
>
> select foo.a
> from foo x;
>
> By adding the alias x the query still workes but gives a different
result.
>
Dennis,
This feature has been addressed many times before.
Please search the archives and refer to Extensions within SELECT doc.
AFAIK it can even be turned off, but don't know how exactly.
As I said, search the archive.
HTH
Regards, Christoph

On Wed, Jul 16, 2003 at 08:29:01 +0200, Dennis Björklund <db@zigo.dhs.org> wrote:
> I had a bug in one of my queries that wasn't detected by pg because if 
> filled in the from clause by itself. Take for example a querie like

Currently this is the only way to use additional tables when doing a delete.