Question

我对学生集合有一个聚合查询，它返回两组结果对于这样的每个学生

{ _id: 1543,
  name: 'Bill Jackson',
  scores: { type: 'homework', score: 38.86823689842918 } }

{ _id: 1543,
  name: 'Bill Jackson',
  scores: { type: 'homework', score: 15.861613903793295 } }

这很好用。现在在回调中我想删除每个学生的一个分数。我使用下面丑陋的嵌套条件来隔离我要删除的两个记录中的哪一个，并且，一旦实现了，我创建了一个查找和修改查询来删除文档，但没有证据表明它已经运行。 findAndModify的错误或成功回调都没有运行，但是我能够记录我在调用findAndModify的区域内。

是否可以在回调中查询数据库中的数据库？如果没有，我应该如何执行在db中持续存在的操作？

                              //aggregation query ommitted
  , function(err, result) {   //callbackstarts here with result of aggregation query that returns two records for each student


   for (var i=0; i<result.length; i++) {

    var id = result[i]['_id'];

    if (id === result[i]['_id']){
        if (foo && foo === result[i]['_id']){
         //if we're in here, we know we need to remove score associated with this result[i]['_id']

          //create findAndModify to remove the record
                var query = { '_id' : result[i]['_id']}
                var sort = []
                var operation = { '$pull' : { 'scores.score' : result[i]['scores']['score'] } };
                var options = []

                console.log('this code is getting called but findAndModify not')

                db.collection('students').findAndModify(query, sort, operation, options,function(err, doc) {
                            if(err) throw err;

                            if (!doc) {
                                console.log("record not found");
                            }
                            else {
                                console.log("changed doc" + doc);
                            }


                        });

        }else {

          var foo = result[i]['_id']  //part of logic to isolate which of two records to remove


           }

findAndModify查询未在回调聚合中执行

0 个答案: