Обсуждение: Re: [HACKERS] distinct. Is this the correct behaviour?

----- Original Message -----
> Hmph, so sybase hasn't thought through the implications of ORDER BY on
> a hidden column vs. DISTINCT either.  Can anyone try it on some other
> DBMSes?
>

Using the following script...
   create table t1(f1 int, f2 int);   insert into t1(f1, f2) values(1,1);   insert into t1(f1, f2) values(1,2);
insertinto t1(f1, f2) values(1,3);   insert into t1(f1, f2) values(2,4);   select distinct f1 from t1 order by f2;
 


Returned the following message under Oracle8 on NT:   ORA-01791: not a SELECTed expression

Returned the following message under MS SQL Server 7.0:   ORDER BY items must appear in the select list if SELECT
DISTINCTis
 
specified.

I could try it on Oracle8i but I suspect the result will be the same.

"Damond Walker" <dwalker@black-oak.com> writes:
> Returned the following message under MS SQL Server 7.0:
>     ORDER BY items must appear in the select list if SELECT DISTINCT is
> specified.

Sure looks like that is the consensus answer to the semantics problem...
guess we should do the same.
        regards, tom lane

> "Damond Walker" <dwalker@black-oak.com> writes:
> > Returned the following message under MS SQL Server 7.0:
> >     ORDER BY items must appear in the select list if SELECT DISTINCT is
> > specified.
> 
> Sure looks like that is the consensus answer to the semantics problem...
> guess we should do the same.

Added to TODO:
* require SELECT DISTINCT target list to have all ORDER BY columns

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