basic question

[Andrew M McDermott]

Robb Hill wrote:
> 
> Hello,
> 
> I have installed grass 5 beta on linux.  I have two sets of polygon data
> and run some simple queries.  After some difficulty, I have been able to
> import the data ok.
> 
> My question is this...
> 
> After looking through all of the commands I cannot see how one asks
> tyipical gis questions like give me all the entities withing a certain
> distance of this point, associating two datasets using a
> "point(centroid) in a polygon" type query.
> 
> Also where is the database aspect of the grass gis system?  Does it have
> one?
> 
> Are these things possible with grass?
> 
They seem to amount to one question, which the web site covers if you
hunt around. There are several database and flat-field options, and you
can construct your own procedures with a little scripting and a DB
server to query. RIM, Postgres 6.3x, and a few others are currently
available among the installable modules (at least in 4.whatever I had
last). Postgres has object variable types which can be used intuitively
with GIS to construct vector files from data.
> Any help is greatly appreciated.  Thanks in advance.
> 
> Thanks,
> Robb Hill