[GRASS-user] the performance of displaying vector attributes - with MySQL no difference!!

[Zbigniew Perski]

On Mon, 2006-11-13 at 19:52 +0100, Jarek Jasiewicz wrote:
> > Hi again,
> > the problem of my database is that I don't see any way to optimize it.
> > Imagine if you have 20 thousands of xyz points and want just to
> > visualize them in different colors (dem-like color scale). Each point
> > has its unique x,y,z values...
> > I tried to assign indexes for my "z" column using:
> >  
> > 	ALTER TABLE my_points ADD INDEX(z_ccordinate);
> >
> > And I don't see any difference in performance with e.g. v.univar.sh 
> > So maybe I am doing something wrong?
> >   
> If I understood well from the previous post threre is a RGB column it is 
> indexed? how much categories of rgb colors you have. If you have as many 
> categories as values this is the problem. In grass, graphical engine 
> must assing color and render every pixel individualy
> 
Right I have tried both: to index my "z" column and then grassrgb as
well. There are 30 categories and I guess it would speed up things.
Maybe I was wrong with indexing?

Thanks

Zbigniew