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From Stanley Iriele <siriele...@gmail.com>
Subject Re: View question
Date Sun, 05 Oct 2014 08:04:39 GMT
Comparing numbers is much faster and cheaper space wise than strings
On Oct 5, 2014 1:04 AM, "Stanley Iriele" <siriele2x3@gmail.com> wrote:

> You would need a view... As I described earlier.... But BE SURE TO store
> the UTC milliseconds on the doc...what...or use the getTime() function to
> emit [ seconds, group]... And then your reduce would be _count.... Lastly
> you will need to write a list function that aggregates over your results on
> last time to get your desired output
> On Oct 5, 2014 12:33 AM, "Boaz Citrin" <bcitrin@gmail.com> wrote:
>
>> how could I solve it if let's say it would be limited to the second?
>>
>> On Sun, Oct 5, 2014 at 10:07 AM, Stanley Iriele <siriele2x3@gmail.com>
>> wrote:
>>
>> > 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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