猫鼬-查询最新文件 [英] Mongoose - Query latest document

问题描述

这似乎是一个基本问题，但我找不到答案.

This seems like such a basic question, but I can't find an answer to it.

我想查询数据库中的最新文档.我为此编写了以下函数，但它不返回最新条目，而是仅返回数据库中的第一个条目.我尝试使用find()而不是findOne()，但是它在数组中返回了一个我不想要的对象.是否有一个本地的mongoose函数以对象的形式返回最新文档?

I want to query for the latest document in my database. I wrote following function for it but it doesn't return the latest entry, instead it just returns the first one in the db. I tried find() instead of findOne() but it returned an object inside an array which isn't what I want. Is there a native mongoose function that returns the latest document in form of an object?

const getLatestRound = module.exports.getLatestRound = function(callback){
    SmallHistory.findOne().limit(1).sort({ date: -1 }).exec((err, data) => {
        if(err) {
            callback(new Error('Error querying SmallHistory (getLatestRound())'));
            return;
        }
        if(data) {
            callback(null, data);
            return;
        }
    });
}

请不要投票:(谢谢

推荐答案

sort()和limit()的顺序错误；在进行反向排序之前，您要先进行限制.更改为:

sort() and limit() are in the wrong order; you're limiting BEFORE your sort backward. Change it to:

SmallHistory.findOne().sort({ date: -1 }).limit(1).exec((err, data) 

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