[GRASS-user] Re: [GRASSLIST:1140] Re: Qn. on extracting from multiple rasters, data corresponding to vector polygons

Hamish hamish_nospam at yahoo.com
Sun Sep 17 05:23:50 EDT 2006


Vishal Mehta wrote:
> 
> 3. i was going to just copy my vector map and then delete the original
> 500 rain columns from the table, and then add the 500 ET columns- but
> i was not able to do it. i tried commands like
>  echo "DELETE COLUMN 'Rain1' FROM watershed8c" | db.execute
> 
> and
> echo "DELETE FROM watershed8c COLUMN LIKE 'rain'" | db.execute
> but they did'nt work.
> 
> How do i delete say all columns that start with the text 'rain' from a
> table?


I'm not sure, but the DBF driver may not support "DELETE" ?
Make a new table, copy columns you want to keep, v.db.droptable the old
table? or use another db?


Hamish




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