Re: ... reporting a bug... asking an SQL question (joins, order by, and group by)

Hi,

Strictly speaking Mckoi should generate an error for the query you tried 
but it doesn't because this is the same way a lot of other SQL database 
systems work.  For your query;

   select *
   from ranked_genre
   group by artist
   order by artist asc, rank asc, created desc;

The 'rank', 'genre' and 'created' data selected from the table is not 
done in a deterministic way.  Adding 'rank' and 'created' to the order 
by clause will not change this.

The final query you came up with seems like a reasonable solution to 
your problem.  I've been trying to think of a simpler solution but I'm 
unable to.

Toby.


Tom Aviv wrote:

> Mckoi folks,
> 
> I think I'm reporting a bug, and I'm certainly asking an SQL question.
> 
> I've reduced the broken query down as much as I have, but still have 
> some SQL to work though to demonstrate my question and what I think is a 
> bug.
> 
> I'm using McKoi very happily and developing a trust network related 
> application.  The application uses information from many users about the 
> same topic and, among other things, shows any user a view of the data 
> according to whom he/she trusts.
> 
> - The users are stating what genre different artists should be
> categorized (as in the I say Beatles are Pop, he says Rock, she says
> Oldies, etc...)
> 
> - Usernames have been replaced by "rank" (higher rank is stronger.)
> 
> For certain views of the data, I just want to show the "best" single 
> answer.  This is the most recent thing that the highest ranking person 
> said.  Discussion continues after entering data.



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