Hi,
I'm looking for the same solution. The main raison of using view filter in 
_changes is to accelerate find out the appropriate modified data (filter in 
_changes not have index, so too slow in large-scale scenario).
I suppose that, our database has 1M documents, I've just deleted 1 document, 
and I'd retrieval this latest modif  without scan previous 1M docs (I don't 
know which _lastseq value to pass through ?since= param).

Do you have any suggestion for this problem ? Jan was totally right, view 
filter doesn't not raise up deleted documents, so no sense in this case.

Special thanks

------------------------
Hong-Thai

-----Original Message-----
From: Jens Alfke [mailto:[email protected]] 
Sent: lundi 8 août 2011 20:14
To: [email protected]
Subject: Re: How to use the changes feed with a view as filter


On Aug 8, 2011, at 5:43 AM, Jeroen van Dijk wrote:

This is the original thread that gave me the impression it should be
possible: http://comments.gmane.org/gmane.comp.db.couchdb.user/13364

According to that thread (and the commit message) this is just a shortcut to 
avoid having to write a filter function that duplicates an existing map 
function.

Jan wrote "This so you can get a notification for when a view *would* be 
updated if you queried it.", but I don't see how that follows. Sure, it will 
tell you when a new revision of a document will appear in the view, but it 
won't tell you when a document that used to be in the view isn't any more 
(because the filter function no longer emitted any rows for it). Being notified 
of only insertions and updates but not deletions doesn't seem useful in 
practice.

-Jens

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