If you only want a few specific fields to be returned for the populated documents, you can accomplish this by passing the field name syntax as the second argument to the populate method. Model .findOne({ _id: 'bogus' }) .populate('the_field_to_populate', 'name') // only return the...
如果对同一路径populate()两次,只有最后一次生效。 // 第二个 `populate()` 覆盖了第一个,因为它们都填充 fansStory.find().populate({path:'fans',select:'name'}).populate({path:'fans',select:'email'});// The above is equivalent to:Story.find().populate({path:'fans',select:'email'}); Qu...
Post.find({title: 'post-by-aikin'}) .populate('poster comments') .exec(function(err, docs) { var opts = [{ path : 'comments.commenter', select : 'name', model : 'User' }]; Post.populate(docs, opts, function(err, populatedDocs) { console.log(populatedDocs[0].poster.name); //...
特别地,So far youve only populated based on the _id field. However, thats sometimes not the right choice. In particular, arrays that grow without bound are a MongoDB anti-pattern. Using mongoose virtuals, you can define more sophisticated relationships between documents. var PersonSchema = ...
Any field with a ref property will be typed as RefDocument["_id"] | RefDocument. As part of the generated file, mongoose will be augmented with Query.populate overloads to narrow return types of populated queries (this can be disabled using the --no-populate-overload flag). A helper ...
Record.find({some_condition:true}).cache(30)// The number of seconds to cache the query. Defaults to 60 seconds..exec(function(err,records){// You are able to use callback or promise...});Record.aggregate().group({total:{$sum:'$some_field'}}).cache(0)// Explicitly passing in ...
doc.set():参数包括path, val, [type], ⚠️path其实就是field名字key/value对儿的key。 doc.validate(): 手动地检测验证(自动在save()前激活) 大多数时候,你需要从你的document得到数据。 使用res.send()把数据发送到一个客户端。 document对象需要使用toObject()和toJSON()转化格式,然后再发送。
注意: mongoose >= 3.6 exposes the original _ids used during population through the document#populated() method. Field Selection 如果我们只想要一些扩展文档的特定的字段?这可以通过传递populate方法的第二个参数一般的字段名语法来完成: Story .findOne({ title:/timex/i }) ...
const mySchema = new Schema({ field: Number }, { strict: true, strictQuery: false // Turn off strict mode for query filters }); const MyModel = mongoose.model('Test', mySchema); // Mongoose will not strip out `notInSchema: 1` because `strictQuery` is false MyModel.find({ not...
Mongoose assigns each of your schemas an _id field by default if one is not passed into the Schema constructor. The type assigned is an ObjectId to coincide with MongoDB's default behavior. If you don't want an _id added to your schema at all, you may disable it using this option....