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// import async to make control flow simplier
var async = require('async');
// import the rest of the normal stuff
var mongoose = require('../../lib');
require('./person.js')();
var Person = mongoose.model('Person');
// define some dummy data
var data = [
{
name: 'bill',
age: 25,
birthday: new Date().setFullYear((new Date().getFullYear() - 25)),
gender: 'Male'
},
{
name: 'mary',
age: 30,
birthday: new Date().setFullYear((new Date().getFullYear() - 30)),
gender: 'Female'
},
{
name: 'bob',
age: 21,
birthday: new Date().setFullYear((new Date().getFullYear() - 21)),
gender: 'Male'
},
{
name: 'lilly',
age: 26,
birthday: new Date().setFullYear((new Date().getFullYear() - 26)),
gender: 'Female'
},
{
name: 'alucard',
age: 1000,
birthday: new Date().setFullYear((new Date().getFullYear() - 1000)),
gender: 'Male'
}
];
mongoose.connect('mongodb://localhost/persons', function(err) {
if (err) throw err;
// create all of the dummy people
async.each(data, function(item, cb) {
Person.create(item, cb);
}, function(err) {
if (err) {
// handle error
}
// alright, simple map reduce example. We will find the total ages of each
// gender
// create the options object
var o = {};
o.map = function() {
// in this function, 'this' refers to the current document being
// processed. Return the (gender, age) tuple using
/* global emit */
emit(this.gender, this.age);
};
// the reduce function receives the array of ages that are grouped by the
// id, which in this case is the gender
o.reduce = function(id, ages) {
return Array.sum(ages);
};
// other options that can be specified
// o.query = { age : { $lt : 1000 }}; // the query object
// o.limit = 3; // max number of documents
// o.keeptemp = true; // default is false, specifies whether to keep temp data
// o.finalize = someFunc; // function called after reduce
// o.scope = {}; // the scope variable exposed to map/reduce/finalize
// o.jsMode = true; // default is false, force execution to stay in JS
o.verbose = true; // default is false, provide stats on the job
// o.out = {}; // objects to specify where output goes, by default is
// returned, but can also be stored in a new collection
// see: http://mongoosejs.com/docs/api.html#model_Model.mapReduce
Person.mapReduce(o, function(err, results, stats) {
console.log('map reduce took %d ms', stats.processtime);
console.log(results);
cleanup();
});
});
});
function cleanup() {
Person.remove(function() {
mongoose.disconnect();
});
}
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