[Qgis-user] Linking tables in QGIS vector objects?

[Agustin Lobo]

Hi!

I have a vector map of land use, I'd like
to know if the following operations can be made
with QGIS:

1. Create a table with a list of the 7 Land use
types that are present so that I can select one land
use and get highlighted all polygons with
that land use.

2. Link this table of 7 land use categories to another table
of, for example, biomass/ha, so that
I can display a map of biomass/ha.

3. Calculate the product of the biomass/ha * ha
of each polygon and get it as a new variable in the
original table for display.

I konw I can do 2 and 3 in R and then bring the output
to QGIS, but would like to know if there is a QGIS way for this,
in particular the link between tables (through Postgis? I've
no idea on how to use it)

Thanks,

Agus

-- 
Dr. Agustin Lobo
Institut de Ciencies de la Terra "Jaume Almera" (CSIC)
LLuis Sole Sabaris s/n
08028 Barcelona
Spain
Tel. 34 934095410
Fax. 34 934110012
email: Agustin.Lobo at ija.csic.es
http://www.ija.csic.es/gt/obster