Re: GEQO: ERX

Is this a TODO item?

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Adriano Lange wrote:
> Hi
> 
> Tobias Zahn escreveu:
> > Hello Adriano,
> > thank you very much for posting your patch. I think it will help to make
> > further work easier, too. I hope you don't mind when I ask you some
> > questions.
> > 
> > When you said that this new approach is worse or equal than GEQO, did
> > you refer to performance or to the quality of results?
> 
> Not exactly this approach, but the implemented (and not configured) 
> algorithm was worse than GEQO in a little test made. I just used a 
> sequence of 8 executions of a query with 18 relations for each 
> algorithm. The costs generated by GEQO was little better than 2PO, in 
> average and standard deviation. But 8 executions and 1 query don't prove 
> anything. I want to make some further tests, but this little difference 
> seems good for me.
> 
> > Why do you think that compressed annealing might be the better approach?
> 
> I don't think if compressed annealing is better or not. I don't read 
> about it yet.
> 
> However, an optimizer can be better in a context but worse in another.
> 
> Regards,
> Adriano
> 
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