----- Original Message Follows -----
From: "Radim Blazek" <radim.blazek@gmail.com>
To: twiens@interbaun.com
Cc: GRASS5 <grass5@grass.itc.it>
Subject: Re: [GRASS5] Layers Clarification
Date: Mon, 6 Mar 2006 17:51:59 +0100
The possibility to keep in a database the relation between
geometry objects in a map and more tables/records was
considered during the development of GRASS 6.0. It does
not appear to be better solutin because all the geometry
processing is done in files. Example: Say that we have
one layer with 2 loverlapping lines linked to 2 records in
one table.
1
+-----------------------+ 2
+-------------------------+
Now we want to clean data and remove the duplicated part,
we run v.clean tool=break,rmdupl result (in current
implementation):
1 1,2 2
+--------------+--------+----------------+
Are you indicating by this example that within a single
layer a geographic object can have more than one link to a
table, or is the result of this operation two layers?
T
--
Trevor Wiens
On 3/6/06, twiens <twiens@interbaun.com> wrote:
> The possibility to keep in a database the relation between
> geometry objects in a map and more tables/records was
> considered during the development of GRASS 6.0. It does
> not appear to be better solutin because all the geometry
> processing is done in files. Example: Say that we have
> one layer with 2 loverlapping lines linked to 2 records in
> one table.
> 1
> +-----------------------+ 2
> +-------------------------+
>
> Now we want to clean data and remove the duplicated part,
> we run v.clean tool=break,rmdupl result (in current
> implementation):
> 1 1,2 2
> +--------------+--------+----------------+
>
Are you indicating by this example that within a single
layer a geographic object can have more than one link to a
table, or is the result of this operation two layers?
More links to a table.
Radim
T
--
Trevor Wiens
Radim Blazek wrote:
On 3/6/06, twiens <twiens@interbaun.com> wrote:
The possibility to keep in a database the relation between
geometry objects in a map and more tables/records was
considered during the development of GRASS 6.0. It does
not appear to be better solutin because all the geometry
processing is done in files. Example: Say that we have
one layer with 2 loverlapping lines linked to 2 records in
one table.
1
+-----------------------+ 2
+-------------------------+
Now we want to clean data and remove the duplicated part,
we run v.clean tool=break,rmdupl result (in current
implementation):
1 1,2 2
+--------------+--------+----------------+
Are you indicating by this example that within a single
layer a geographic object can have more than one link to a
table, or is the result of this operation two layers?
More links to a table.
I mùust be very dense, but then what does this have to do with layers ? Everything you do above is in one layer, or ?
Moritz