[GRASS5] db.xxx v.db.xxx question

peter.loewe at gmx.de peter.loewe at gmx.de
Wed Apr 13 04:15:09 EDT 2005


dear all,

i am trying to connect several databases to a vector-layer (DBF-database).

here's the scenario: there are point-vectors (sites), which have a cat-value
and an additional integer value X.
There's also a huge DBF database ("B") with additional content for the
point-vectors.
Linking the additional database with v.db.connect to the vector is no
problem (as layer 2), but how is the key-value set correctly ?

The original database uses the CAT-value as the key-value and apparently
there is no way to fiddle with this.

Hooking up database "B", the column X_ID (holds the same values as column X
in the original vector-database) is declared as _key_.

What is lacking is the referencing of the keys: 
Let's say, the CAT-values range from 1 to 10, while the X-values are
distributed at random between 1000 - 2000.
It would be great if a mouse-based-query to "site 1" [CAT == 1, X == 42]
would select the correct row in database B [where X_ID == 42, Type == "great
place"].

How can this be done ?

Peter 

-- 
Dr. Peter Löwe

Diplom-Geograph

<loewe at geomancers.net>
<peter.loewe at gmx.de>

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