如何限制退回商品的数量? [英] How do I limit the number of returned items?

问题描述

myModel.find({}, function(err, items) {
    console.log(items.length);    // Big number
});

如何将退回的商品限制为最近插入的 10 件商品?

How can I limit the returned items to only the latest 10 items that were inserted?

推荐答案

在最新的 mongoose(撰写本文时为 3.8.1)中，您做的两件事有所不同:(1) 您必须将单个参数传递给 sort()，它必须是一个约束数组或只是一个约束，并且 (2) execFind() 已经消失，取而代之的是 exec().因此，使用 mongoose 3.8.1 你会这样做:

In the latest mongoose (3.8.1 at the time of writing), you do two things differently: (1) you have to pass single argument to sort(), which must be an array of constraints or just one constraint, and (2) execFind() is gone, and replaced with exec() instead. Therefore, with the mongoose 3.8.1 you'd do this:

var q = models.Post.find({published: true}).sort({'date': -1}).limit(20);
q.exec(function(err, posts) {
     // `posts` will be of length 20
});

或者你可以像这样简单地将它链接在一起:

or you can chain it together simply like that:

models.Post
  .find({published: true})
  .sort({'date': -1})
  .limit(20)
  .exec(function(err, posts) {
       // `posts` will be of length 20
  });

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