Ultimately what I am trying to do is to make a varchar(5) field be a varchar(8) field — but I don't see how to do this directly. So, I thought if I created a new varchar(8) column, copied the values of the varchar(5) column into it (This all worked fine); then, renamed the varchar(5) column to 'foo' (which also worked), then I could rename the varchar(8) column to what the column name was for the original varchar(5) column — this does NOT work. Also, I would like to delete the 'foo' column, but I don't see how to do this.
Any suggestions?
Thanks,
Tom
--
Thomas E Adams
National Weather Service
Ohio River Forecast Center
1901 South State Route 134
Wilmington, OH 45177
Quick trick to try then is to open the dbf with OpenOffice you'll see the column specs is the 1st line with the column name. Just change the 5 to an 8. Or do the copy method you mentioned.
I've never seen another way to easily do it. You should think about changing to sqlite though, I was under this impression that it was the default for 6.3
Alex
Thomas.Adams@noaa.gov wrote:
Alex,
dbf; just the default for a generic vector file. I should have added more detail, such as that I am using GRASS 6.3 on Linux.
Thanks,
Tom
----- Original Message -----
From: Alex Mandel <tech_dev@wildintellect.com>
Date: Wednesday, August 13, 2008 10:55 pm
Subject: Re: [GRASS-user] Trying to rename a column
Thomas Adams wrote:
List:
Ultimately what I am trying to do is to make a varchar(5) field
be a
varchar(8) field — but I don't see how to do this directly. So, I thought if I created a new varchar(8) column, copied the values
of the
varchar(5) column into it (This all worked fine); then, renamed
the
varchar(5) column to 'foo' (which also worked), then I could
rename the
varchar(8) column to what the column name was for the original varchar(5) column — this does NOT work. Also, I would like to
delete the
'foo' column, but I don't see how to do this.
Any suggestions?
Thanks,
Tom
What's the data backend you're using? dbf, sqlite, postgis?
Ultimately what I am trying to do is to make a varchar(5) field be a varchar(8) field — but I don't see how to do this directly. So, I thought if I created a new varchar(8) column, copied the values of the varchar(5) column into it (This all worked fine); then, renamed the varchar(5) column to 'foo' (which also worked), then I could rename the varchar(8) column to what the column name was for the original varchar(5) column — this does NOT work.
Paste the exact command with an error message, v.info -c of the vector
map for which the command fails, your GRASS version and platform.
Also, I would like to delete the 'foo' column, but I don't see how to do this.
v.db.dropcol (it's been available since GRASS 6.3). If you don't have
it you can just fetch it from GRASS SVN [1], put somewhere on your
executable path and call it from GRASS, or use such a command:
echo "ALTER TABLE $table DROP COLUMN $col" | db.execute