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POPulling out latest (multiple) entries from MongoDB
 

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  1. POPulling out latest (multiple) entries from MongoDB
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    <p>I am trying to retrieve information on how many attempts a user takes to solve a particular problem as a JSON from a mongodb database. If there are multiple attempts on the same problem, I would only like to pull out the last entry - for instance, right now, if I do a db.proficiencies.find() - I will pull out entries A, B, C, and D but I would like to only pull out entries B and D (latest entries for the problems maze and circle respectively).</p> <p>Is there an easy way to do so?</p> <pre><code>Entry A { "problem": "maze", "courseLesson": "elementary_one, 1", "studentId": "51ed51d0fcb4cc3696000001", "studentName": "Sarah", "_id": "51ed51defcb4cc3696000011", "__v": 0, "date": "2013-07-22T15:38:06.259Z", "numberOfAttemptsBeforeSolved": 1 } Entry B { "problem": "maze", "courseLesson": "elementary_one, 1", "studentId": "51ed51d0fcb4cc3696000001", "studentName": "Sarah", "_id": "51ed51defcb4cc3696000011", "__v": 0, "date": "2013-07-27T15:38:06.259Z", "numberOfAttemptsBeforeSolved": 1 } Entry C { "problem": "circle", "courseLesson": "elementary_one, 1", "studentId": "51ed51d0fcb4cc3696000001", "studentName": "Sarah", "_id": "51ed51defcb4cc3696000011", "__v": 0, "date": "2013-07-22T15:38:06.259Z", "numberOfAttemptsBeforeSolved": 2 } Entry D { "problem": "circle", "courseLesson": "elementary_one, 1", "studentId": "51ed51d0fcb4cc3696000001", "studentName": "Sarah", "_id": "51ed51defcb4cc3696000011", "__v": 0, "date": "2013-07-27T15:38:06.259Z", "numberOfAttemptsBeforeSolved": 4 } var ProficiencySchema = new Schema({ problem: String , numberOfAttemptsBeforeSolved: {type: Number, default: 0} //refers to which lesson, e.g. elementary_one, 2 refers to lesson 2 of elementary_one , courseLesson: String , date: {type: Date, default: Date.now} , studentId: Schema.Types.ObjectId , studentName: String }) </code></pre>
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