Re: [HACKERS] Re: subselects

>
> Bruce wrote:
> > I have completed adding Var.varlevelsup, and have added code to the
> > parser to properly set the field. It will allow correlated references
> > in the WHERE clause, but not in the target list.
>
> select i2.ip1, i1.ip4 from nameip i1 where ip1 = (select ip1 from nameip
> i2);
> 522: Table (i2) not selected in query.
> select i1.ip4 from nameip i1 where ip1 = (select i1.ip1 from nameip i2);
> 284: A subquery has returned not exactly one row.
> select i1.ip4 from nameip i1 where ip1 = (select i1.ip1 from nameip i2
> where name='zeus');
> 2 row(s) retrieved.
>
> Informix allows correlated references in the target list. It also allows
> subselects in the target list as in:
> select i1.ip4, (select i1.ip1 from nameip i2) from nameip i1;
> 284: A subquery has returned not exactly one row.
> select i1.ip4, (select i1.ip1 from nameip i2 where name='zeus') from
> nameip i1;
> 2 row(s) retrieved.
>
> Is this what you were looking for ?
>
> Andreas
>
>

Yes, I know other engines support subqueries and references in the
target list. I want to know if we are going to do that for 6.3.
Personally, I have never seen much use for it.

--
Bruce Momjian
maillist(at)candle(dot)pha(dot)pa(dot)us