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From Nathan Vander Wilt <nate-li...@calftrail.com>
Subject Re: Change in date handling from 1.0.x to 1.2
Date Wed, 19 Sep 2012 20:01:09 GMT
On Sep 18, 2012, at 9:02 PM, Daniel Myung wrote:

> Is there some type of bytecode or something cached somewhere for design
> docs for view functions that could possibly explain how my removal of the
> _design directory could still yield the same original result?
> 

Sorry, I don't have authoritative documentation references on this, but my understanding is
that this is how it works:

1. Removing a _design document does not remove generated views, unless you run view cleanup
2. CouchDB stores generated views on disk based on a hash of the view's *code*

One benefit of this is that in production you can rebuild a new view e.g. _design/app-new
while still fetching old results from _design/app, then switch the names once the new view
has caught up. (IIRC, there may also be some optimization within a _design doc so identical
map functions can be reused between different reduction functions?)

Anyway, it sounds like what happened is that because your view code didn't actually change
(just its behaviour due to JS library differences) this edge case meant that CouchDB assumed
your view was already caught up with most of your database's _changes. Adding a newline to
the view did change its "identity", and so was a reasonable way to trigger view generation.
The other way would have been, while your _design document was temporarily removed, to clean
up views.

hth,
-natevw




> 
> On Mon, Sep 17, 2012 at 9:18 PM, Paul Davis <paul.joseph.davis@gmail.com>wrote:
> 
>> I agree with Bob. This is a difference in your Spidermonkey library.
>> 
>> On Mon, Sep 17, 2012 at 5:47 PM, Robert Newson <rnewson@apache.org> wrote:
>>> I think it's to do with the version of Spidermonkey you've used,
>>> rather than CouchDB version.
>>> 
>>> B.
>>> 
>>> On 17 September 2012 23:35, Cory Zue <czue@dimagi.com> wrote:
>>>> Hi,
>>>> 
>>>> We're in the process of migrating our app from couch 1.0 to 1.2.
>>>> Seeing different behavior in this view function though, which is
>>>> giving us some trouble.
>>>> 
>>>> 
>> https://github.com/dimagi/core-hq/blob/master/corehq/couchapps/formtrends/views/form_time_by_user/map.js
>>>> 
>>>> It looks like it works as designed in 1.0 but in 1.2
>>>> submit_time.getDay() and submit_time.getHours() both return null.
>>>> 
>>>> Is there a better way to handle this now?
>>>> 
>>>> Our dates are formatted like this: 2011-03-07T20:27:12Z
>>>> 
>>>> Cory
>> 


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