_sum
instead of
> function(keys, values, rereduce){
> return sum(values);
> }
I think the wiki is missing some information on build-in reduce functions. I'll
add this today.
On 11.05.2010, at 10:04, Manokaran K wrote:
> Hi,
>
> Am testing an app where there are approx 400k docs (exam results). There are
> only two views in the design_doc:
>
> map:
> function(doc) {
> if(doc.dtype === 'result'){
> var subject_total, scr, scores = doc.scores;
> var total = 0, len = scores.length; //scores.length is 6 to 12
> for(var i=0; i<len; i++){
> scr = scores[i];
> subject_total = scr.th + (scr.pr ? scr.pr : 0);
> total += subject_total;
> emit([scr.code, subject_total], 1);
> }
> emit(['to', total], 1);
> }
> }
>
> reduce:
> function(keys, values, rereduce){
> return sum(values);
> }
>
> I use the above map-reduce to calculate the frequencies for each subject
> score as well as the aggregate score.
>
> My problem is that to it takes a looong time to generate the view. After two
> hours (on a dual core 2.2GHz with 3GB RAM) only 300K docs have been
> indexed!! Is that on par? Or is something wrong?
>
> Sometime back JChris had mentioned using the erlang 'sum' call to speed up
> things in response to another mail but I cannot locate that now. Can
> someone point me to it?
>
> I have one other view in the design_doc:
>
> map:
> function(doc) {
> if(doc.dtype === 'subject_def'){ //only about 20-25 docs of this
> type
> val = {};
> for(var prop in doc){
> if(prop !== '_id' && prop !== '_rev' && prop !== 'dtype'){
> val[prop] = doc[prop];
> }
> }
> emit(doc._id, val);
> }
> }
>
> No reduce for this.
>
>
> Thanks,
> mano
>
>
>
> --
> Lord, give us the wisdom to utter words that are gentle and tender, for
> tomorrow we may have to eat them.
> -Sen. Morris Udall
