[Zope-dev] ZCatalog searching for missing values

Stephan Richter srichter@cbu.edu
Mon, 08 Oct 2001 10:33:16 -0500


>I just tried out ZOQLMethod as well.  Couldn't get it to work, but it
>looks like really solid craftsmanship.  I like the user-friendly way of
>selecting base object and the complete syntax. :)  Some questions:
>
>1. I couldn't get any query to work.  I keep getting
>
>         exceptions.TypeError
>         argument 2 to map() must be a sequence object

Solved. See below.

>Here's an example query that I've tried
>
>         SELECT id
>           WHERE title == ''
>           RECURSIVE;

You can only select meta types (this is by design; I just don't want to 
deal with brains and all that stuff right now.)!! Did you see the help? It 
has a long example in there as well.
But there is another bug. You have to specify FROM right now. I will fix 
that. Okay, is fixed for the next release.

So,

SELECT "DTML Method"
   FROM "."
   WHERE title == ''
   RECURSIVE;

should work.

>2. Is the ZCatalog searching implemented?  How do I activate it?

Yes, see the "Rather Lengthy Example".

>3. Do you have any plans to implement JOIN?

No, for the reasons given above. You select only objects, not attributes.

BUT, patches are always welcomed!!! :-)

>The exists function would be very cool.

I will look into this. Hopefully it will be not too hard to implement.

>Keep up the great work.  Hope this helps flush out some features :)

I hope I will. :-) Yes it does. If you and all the other Zope people could 
write me some arguments to support attribute selection, then I will look 
into it (but it will be not that easy).

Regards,
Stephan

--
Stephan Richter
CBU - Physics and Chemistry Student
Web2k - Web Design/Development & Technical Project Management