[Zope] Error Value: len() of unsized object at SQL method

[Thomas B. Passin]

Use <dtml-try>....</dtml-except>.

If you get no result, there is no sequence to loop over with dtml-in, that's
why you get an error.  Still, I don't get this problem using ZODBC and Zope
2.3.3 on Windows.  If there is no data, dtml-in simply has no rows to loop
over, but it doesn't give an error.  So the returned data object includes an
empty sequence, while in your case there is no sequence.  Maybe it depends
on the particular database adapter you are using.

Cheers,

Tom P

[Kerekes Lajos]
>
> I have an SQL select. If it gives no result, I get this error message
> Error Type: TypeError
> Error Value: len() of unsized object
>
> How can I manage it?
>  I tried this:
> <dtml-in ZSQLSelect>
> foo, bar.....
> <dtml-else>
> no result
> </dtml-in>
>
> but still get the error.
>