[GRASS-user] Re: using v.colors- suggestion of using a sqlite suggestion

[Achim Kisseler]

Hello Luisa,

(see below)

Am 17.11.2010 16:21, schrieb Luisa Peña:
> Hello achim
> 1- I converted from raster to vector (r.to.vect)
> r.to.vect -v input=teste01_LULC at Regional output=vector01 feature=area
> Extracting areas...
> Building topology for vector map <vector01>...
> Registering primitives...
> 833 primitives registered
> 4624 vertices registered
> Building areas...
> 334 areas built
> 163 isles built
> Attaching islands...
> Attaching centroids...
> Number of nodes: 662
> Number of primitives: 833
> Number of points: 0
> Number of lines: 0
> Number of boundaries: 499
> Number of centroids: 334
> Number of areas: 334
> Number of isles: 163
> r.to.vect complete.
>
> 2- When I select a designated area i get this:
> East: 629238.662505
> North: 9331859.599043
> Map: vector01
> Mapset: Regional
> Type: Area
> Sq Meters: 1132124355.009
> Hectares: 113212.436
> Acres: 279754.021
> Sq Miles: 437.1157
> Layer: 1
> Category: 5
> Driver: dbf
> Database: C:\DWEISdata/Brazil/Regional/dbf/
> Table: vector01
> Key column: cat
> cat : 5
> label :
> (CAT IS the value of my previous raster)
>
> 3- When i do:
> v.db.connect map=vector01 at Regional table=vector01 driver=sqlite
> I get the following error:
> ERROR: Use -o to overwrite existing link for layer <1>
> THis will mean that it will overwrite existing table right?
>
> I tried with -o and I got the error:
> DBMI-SQLite driver error:
> Unable to open database: unable to open database file
> Unable to open database <$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/> by
> driver <sqlite>
> Unable open database <$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/> by driver
> <sqlite>
> ERROR: Table <vector01> does not exist in database
> <$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/>
> So I'm not able to do what you suggest

That means, that no sqlite-db is established.
<$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/>  is a folder for the dbf-db. A 
sqlite-db is only one file. You can use one of many programs to create 
an empty one (eg. there is an firefox add-on that can do that).

Store the db (eg. "myname.sqlite") in you gis-folder and connect (in 
this example case) to:
$GISDBASE/myname.sqlite

Best regards,
Achim

>
> Any other suggestion?
>
> 2010/11/16 Achim Kisseler <ak7 at jupiter.uni-freiburg.de
> <mailto:ak7 at jupiter.uni-freiburg.de>>
>
>     Hi,
>
>     you should not loose the information, because the table you create
>     consists of a column "cat" by default containing the cats.
>
>     Does this do the job?
>
>     Achim
>
>     Am 16.11.2010 09:46, schrieb Luisa Peña:
>
>         Hi Achim
>         Well, the thing is, if I add a table to my vector, I will loose
>         all the
>         information that is already available in my vector (since it's a
>         conversion from a Classification raster I have a cat value for each
>         area). Right?
>
>         2010/11/15 Achim Kisseler <ak7 at jupiter.uni-freiburg.de
>         <mailto:ak7 at jupiter.uni-freiburg.de>
>         <mailto:ak7 at jupiter.uni-freiburg.de
>         <mailto:ak7 at jupiter.uni-freiburg.de>>>
>
>
>
>
>             Am 15.11.2010 16:41, schrieb Luisa Peña:
>
>                 In this email,
>         http://lists.osgeo.org/pipermail/grass-user/2010-November/058644.html,
>                 you suggested me to use sqlite as database. I'm willing
>         to try
>                 that. How
>                 can I do that with a vector created from r.to.vect with
>         categories
>                 values in cat column
>
>
>             Hi Luisa,
>
>             first create an sqlite-database, second take the vector file
>         and add
>             an table to it
>             (http://grass.osgeo.org/gdp/html_grass64/v.db.addtable.html:
>             --%<--
>             DESCRIPTION
>             v.db.addtable creates and adds a new attribute table to a given
>             vector map. It links the table to the specified layer of the
>         vector
>             map. If the vector map is not yet linked to any table, new a
>             database link is established based on the MAPSET database
>         settings
>             (see db.connect).
>             --%<--).
>             Is that what you are looking for?
>
>             Regards,
>             Achim
>
>
>