It work at level of inserting data in the database. It works if the
input contains the data needed for the computation.
On Dec 21, 5:42 pm, Vinicius Assef <vinicius...@gmail.com> wrote:
> As book says...
> "DAL fields may have a compute attribute. This must be a function (or
> lambda) that takes a Row object and returns a value for the field."
>
> So, lambda for computed fields gets all fields and returns just one field.
>
> I think it work on DAL level, not on FORM level.
>
> On 12/19/11, Richard Vézina <ml.richard.vez...@gmail.com> wrote:
>
>
>
>
>
>
>
> > I don't get all my db.table fields form define_table fields defined...
>
> > A other guy report that... But didn't find exactly why his compute
> > functions as stop working properly...
>
> > To me it's related to the fact tha if I do :
>
> > Field('mycomputefield', compute=lambda r: r)
>
> > I am not getting all the fields.
>
> > For example:
>
> > db.define_table('test1',
> > Field('f1','string'),
> > Field('f2','integer'),
> > Field('computefield',compute=lambda r: r))
>
> > Will return only field that appear in form, so if I set f1 to
> > writable=False, it will not be in form so it will not be available to
> > compute function...
>
> > I think it for make compute failed silently if some fields are set to
> > writable or readable = False... But I would return all the field to compute
> > with a "None" for empty field instead of not returning any key... I really
> > don't know if it even possible, if it is a bug or something else...
>
> > I work around issue I were having with compute (I would compute a md5 hash
> > for row so I would have all key/value pairs even if one of those were
> > empty, but I can't with compute), so I use the new virtual field style
> > (hope it will stay).
>
> > Here the thread I am refering to :
> >http://groups.google.com/group/web2py/browse_thread/thread/cd6191f982...
>
> > Richard
>
> > On Mon, Dec 19, 2011 at 2:22 PM, Anthony <abasta...@gmail.com> wrote:
>
> >> What do you mean it doesn't return all the fields?
>
> >> On Monday, December 19, 2011 10:47:42 AM UTC-5, Richard wrote:
>
> >>> Hello,
>
> >>> I try to use compute to generate a record md5_hash on insert and
> >>> update, but I discover that compute=lambda r: don't return all the
> >>> db.table fields why?
>
> >>> Thanks
>
> >>> Richard
