Question

I would like to know what is the best way to do the following.

I store data of what a person has done in Mongodb like a log

e.g.

{
 "date":"01-01-2002T08:20:30",
 "task":"contact-lead",
 "user":"username"
}

What I need is to count how many tasks where done in that day and put them in a graph like Highstock.

Answer 1

The command bellow will aggregate/count the number of tasks per day:

db.col.group({
    $keyf : function(doc) {
        return { "day" : doc.date.getFullYear() + "/" + (doc.date.getMonth()+1) + "/" + doc.date.getDate() };
    },
    initial: {count:0},
    reduce: function(obj, prev) { prev.count++; }
})

Then you just format them if needed and send it to highcharts API, but be careful because if you have a lot of data that can be slow.

The other option is to use MapReduce and periodically update the aggregate collection and use that as a source for your graphs.