Re: newbie question - writing derived view back to db

Derived views are not persistent views.  If you want to have a view
ordered on a particular column and to have that view be persistent,
you must use the view.ordered() function, i.e.

view = st.getas("test[a:i,b:s]").ordered(1)

Now all data appended to view will be ordered on the first column.

view.sort()

creates an ordered view but this has no effect on the database.  If
you have done a special operation that you want to save, your best bet
is to create a new view with the same table properties,

i.e.

vw2 = st.getas("test_save[a:i,b:s"])

for row in view:
     vw2.append((row.a, row.b))

You can simplify this somewhat using a special class such as

class _wrap_row:
    def __init__(self, row): self._row =row
    def __getattr__(self, key): reteurn getattr(self._row, key)

for row in view:
    vw2.append(_wrap_row(row))

so you don't actually have to spell out row.a, row.b

If you are lucky you might be able to simply do

for row in view:
    vw2.append(row)

but this doesn't work on all versions of python.

I am in the process of patching the python wrapper so you can simply
insert a view into a compatible view, but you can use this work around
until then.

Brian
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