[GRASS5] v.db.updatecol and v.db.addcolumn

[Moritz Lennert]

On Wed, May 25, 2005 11:49, Radim Blazek said:
> Moritz Lennert wrote:
>> Hello,
>> As I mentioned in a separate mail, I agree with Daniel that using external
(point-and-click) tools might not be the best way for GRASS attribute
management.
>> So, here are two small modules which interface db.execute for specific tasks,
>> respectively adding a column and updating a column value. Others might follow
>> according to need.
>> Any feedback welcome.
>> Moritz
>
> Good, I'll use both.
>
> v.db.addcolumn
> --------------
>
> I think that v.db.addcolumn should support the possibility to add more
columns in one step. It is however dangerous (name - type order for more
columns) to have column names and typse in 2 separated options. I suggest
one option columns in format
>
> columns="name1 type1[, name2 type2, ...]"
>
> the same option is already used in v.in.ascii.
>
> Do you think that it is too difficult for users to write
>
> columns="newcol integer"
>
> instead of
>
> colname=newcol coltype=integer
>

No I guess it is not too difficult, although I have actually been thinking in
a different, even simpler direction where the user wouldn't enter the type,
but chose it from a drop-down menu. Is this realistic or are the available
types different for every database backend ?

This said, if I implement your suggestion: can this be done in one alter table
command (and if yes could you show me since I can't seem to find out how), or
would this be one alter command for each new column (not difficult to code
either) ?


> v.db.update
> -----------
>
> If possible, we should use the same names of options which are already used
in existing modules.
>
> AFAIK in existing modules is used 'column', not 'colname'.
>
> Also 'sqlwhere' should be replaced by simple 'where' which is used in many
other modules.
>

I'll correct that.

Thanks !

Moritz