It's this;
map:
function(doc) {
emit(doc.date.expire, null);
}
and there is no reduce function.
query with ?startkey="today's date minus 30 days encoded in same
format as doc.date.expire", and same for 60 and 90.
And remember to ensure that doc.date.expire sorts in the right order.
Perhaps emit it as new Date(doc.date.expire).getTime() or in ISO-8601
formatted string.
B.
On 20 September 2012 08:04, Carl Bourne <[email protected]> wrote:
> Jens,
>
> Understand!
>
> So I guess then the only way to do this is using 3 separate queries with
> startkey, endkey for each time period? Then assemble the results externally
> using whatever performed the query?
>
> Are there any other options?
>
> Regards,
>
> Carl
>
>
> On 20 Sep 2012, at 01:18, Jens Alfke <[email protected]> wrote:
>
>> This isn’t a valid map function, because it’s not purely functional — it
>> uses external input in the form of the current date/time. So if the map
>> function is run twice on the same document, it will not always emit the same
>> output. That’s not allowed.
>>
>> In other words, think of what happens if you generate the index now, and
>> then query it 90 days from now. The information in the index probably won’t
>> be valid because everything will have expired already, right? But CouchDB
>> has no idea the index is time-sensitive, so it’s going to return you the old
>> data anyway. You just cannot put time-sensitive data into a map function.
>>
>> Instead what you should be doing in the map is writing out the expiration
>> times of the documents. Then at query time you can see how far in the future
>> those are.
>>
>> —Jens
>
