conditional/regular expressions are slow

[Douglass Davis]

Paul Ramsey wrote:

>
> The answer is your open 2 below.  Pre-process your data so that  
> mapserver can do the bare minimum of work for each rendering pass.   
> There is no point in having mapserver read 100000 features that it is  
> not even going to draw.
>
> Paul
>

thanks.  Does any one know of any free tools that can separate a 
shapefile into multiple shapefiles using queries/regular 
expressions/attributes...?