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From Stanley Iriele <siriele...@gmail.com>
Subject Re: View question
Date Sun, 05 Oct 2014 07:07:18 GMT
Or can it be down to say....the hour... Or minute... Something like that
On Oct 4, 2014 11:53 PM, "Boaz Citrin" <bcitrin@gmail.com> wrote:

> I need to filter by date and group by group...
>
> For example having these docs:
> {
>   "group" : "a",
>   "associated" : "2014-10-04T21:58:59.377Z",
>  ...
> }
> {
>   "group" : "a",
>   "associated" : "2014-10-03T21:58:59.377Z",
>  ...
> }
> {
>   "group" : "b",
>   "associated" : "2014-10-04T21:58:59.377Z",
>  ...
> }
> {
>   "group" : "b",
>   "associated" : "2014-10-01T21:58:59.377Z",
>  ...
> }
>
> I want to support a query with from-date = "2014-10-02T21:58:59.377Z"
> to-date= "2014-10-04T22:58:59.377Z"
>
> And the result will be -
>
> a, 2
> b, 1
>
>
>
>
> On Sun, Oct 5, 2014 at 9:36 AM, Stanley Iriele <siriele2x3@gmail.com>
> wrote:
>
> > Right ...are you saying... That you need grouping down to the day?... In
> > which case you can just emit[ date, group]... The fate being the
> > milliseconds truncated to the day and just have a reduce that's
> _count....
> > By the way the date can also be broken down to [year, month, day, group]
> >
> > You would need to change the group_level to 4 instead of 2 bit the view
> > would be human readable.
> >
> > The truck here is that you query with start key ,end_key to get the the
> > days and re reduce those values again for that arbitrary date range in a
> > reduce function and you should be good
> > On Oct 4, 2014 11:23 PM, "Boaz Citrin" <bcitrin@gmail.com> wrote:
> >
> > > I need to get the count of document that were associated to a group
> > between
> > > two given dates. Thanks!
> > >
> > > On Sun, Oct 5, 2014 at 8:13 AM, Stanley Iriele <siriele2x3@gmail.com>
> > > wrote:
> > >
> > > > Hey what date are you looking to filter to? Day/ month..year?
> > > > On Oct 4, 2014 10:11 PM, "Boaz Citrin" <bcitrin@gmail.com> wrote:
> > > >
> > > > > Thanks Giovanni,
> > > > > You say I can get all the groups at the same time,
> > > > > but how can I achieve this and also filter by date?
> > > > >
> > > > > On Sun, Oct 5, 2014 at 4:04 AM, Giovanni P <fiatjaf@gmail.com>
> > wrote:
> > > > >
> > > > > > You can use the second with group_level=1 and get all the groups
> at
> > > the
> > > > > > same time.
> > > > > > And you can use _count instead of _sum, so you don't even need
to
> > > emit
> > > > > any
> > > > > > value, just the key.
> > > > > >
> > > > > > On Sat, Oct 4, 2014 at 8:24 PM, Boaz Citrin <bcitrin@gmail.com>
> > > wrote:
> > > > > >
> > > > > > > Hello,
> > > > > > >
> > > > > > > My documents contain two fields to maintain group associations,
> > say
> > > > > > "group"
> > > > > > > holds the group document id, and "associated" holds the
date
> this
> > > > > > document
> > > > > > > was added to the group.
> > > > > > > Now I want to be able to know how many documents were added
to
> a
> > > > given
> > > > > > > group[s] between two given dates.
> > > > > > > The challenge is that to be able to filter by dates, I
need to
> > have
> > > > the
> > > > > > > date as the key first part.
> > > > > > > But I also need the group as the first key part in order
to
> > > aggregate
> > > > > the
> > > > > > > number of group associations.
> > > > > > >
> > > > > > > So I see two options here:
> > > > > > >
> > > > > > > 1.
> > > > > > > Map: associated, {"group": group}
> > > > > > > Reduce: a function that aggregates all values by group,
which I
> > > > assume
> > > > > is
> > > > > > > fine as I know the number of groups is relatively small.
> > > > > > > (plus configuring reduce_limit=false ...)
> > > > > > >
> > > > > > > 2.
> > > > > > > Map: [group,associated], 1
> > > > > > > Reduce: sum(values)
> > > > > > > Here I cannot retrieve multiple groups at once, so I use
a
> > request
> > > > per
> > > > > > > desired group.
> > > > > > >
> > > > > > > Tried the two approaches, with the first one gives faster
> > response.
> > > > > Which
> > > > > > > leads me to two questions:
> > > > > > > 1. Is there any risk in a reduce function that produces
a
> > > potentially
> > > > > > long
> > > > > > > string?
> > > > > > > 2. Is there a better way to achieve what I do here?
> > > > > > >
> > > > > > > Thanks!
> > > > > > >
> > > > > > > Boaz
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>

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