exports.basic = function(){ var map = function(){ var key = { app: this .properties.YA0token, uuid: this .properties.distinct_id // for registered user, using user:account } var value = { register:0, login:0, payment:0, transaction:0 }; if ( this .event== 'register' ) { value.register = 1; } else if ( this .event== 'login' ) { value.login = 1; } else if ( this .event== 'YA0charge' ) { value.payment = this .properties.amount; value.transaction = 1; } print(value.register,value.login,value.payment,value.transaction); emit(key,value); } var reduce = function(key,values){ var result = { register:0, login:0, payment:0, transaction:0 }; values.forEach(function(value){ result.register += value.register; result.login += value.login; result.payment += value.payment; result.transcation += value.transcation; print( 'value:' ,value.register,value.login,value.payment,value.transaction); }); return result; } var options = { // out:{reduce: "mr_users" }, // reduce : add the value of same key out:{merge: "mr_users" }, query:{ "event" :{$in:[ "register" , "login" , "YA0charge" ]}, "properties.time" : { "$gte" : new Date( "9 1 2013" ), "$lt" : new Date( "9 3 2013" )} } } eventCollection.mapReduce(map,reduce,options,function (err, collection2) { logger.info( 'MapReduce for basic is done.' ); collection2.find().toArray(function(err,item){ logger.silly(item); }); }); }