node.js - 蒙古语或蒙古语 native 不支持群组功能？

Question

各位

在node.js中，蒙古语或mongo-native不支持组功能？

mongo 原生代码，

var mongodb = require('mongodb');
var Db      = mongodb.Db;
var Server  = mongodb.Server;
var db  = new Db( "test", new Server( "localhost", 27017 ), { w:0 } );

db.collection( "user" ).group( {
    key: { },
    reduce: function ( curr, result ) { },
    initial: { }
} );

结果，

/node/ex1/node_modules/mongodb/lib/mongodb/collection.js:1400
      if(err != null) return callback(err);
                             ^
TypeError: undefined is not a function
    at Collection.group.scope (/node/ex1/node_modules/mongodb/lib/mongodb/collection.js:1400:30)
    at Db._executeQueryCommand (/node/ex1/node_modules/mongodb/lib/mongodb/db.js:1812:12)
    at Collection.group (/node/ex1/node_modules/mongodb/lib/mongodb/collection.js:1399:13)
    at Object.<anonymous> (/node/ex1/repository.js:34:25)

<小时/>

和蒙古代码，

var Mongolian   = require( "mongolian" );
var server  = new Mongolian;
var db      = server.db( "test" );

db.collection( "user" ).group( {
    key: { },
    reduce: function ( curr, result ) { },
    initial: { }
} );

结果，

db.collection( "user" ).group( {
                        ^
TypeError: Object Mongolian[mongo://localhost:27017]/assistor.user has no method 'group'
    at Object.<anonymous> (/node/ex1/repository.js:77:25)

Answer 1

如the docs中所示，它受 native 驱动程序支持，但 group 方法将 key、reduce 等作为单独的参数，而不是对象中的字段，例如shell 的作用是:

db.collection("user").group(
    {},
    {},
    { sum: 0 },
    function (curr, result) { },
    function (err, result) {
        // Process the result
    }
);