当前的实现全部都是基于 Mongoose 完成的
var mongoose = require('mongoose'),
Schema = mongoose.Schema
var PersonSchema = new Schema({
name: String,
age: Number,
stories: [{
type: Schema.Types.ObjectId,
ref: 'Story'
}]
});
var StorySchema = new Schema({
_creator: {
type: Schema.Types.ObjectId,
ref: 'Person'
},
title: String,
fans: [{
type: Schema.Types.ObjectId,
ref: 'Person'
}]
});
var Story = mongoose.model('Story', StorySchema);
var Person = mongoose.model('Person', PersonSchema);
var aaron = new Person({
name: 'Aaron',
age: 100
});
aaron.save(function(err) {
if (err) return handleError(err);
var story1 = new Story({
title: "Once upon a timex.",
_creator: aaron._id // assign an ObjectId
});
story1.save(function(err) {
if (err) return handleError(err);
// thats it!
});
})
Story
.findOne({
title: /timex/
})
.populate('_creator')
.exec(function(err, story) {
console.log(story)
if (err) return handleError(err);
console.log('The creator is %s', story._creator.name); // prints "The creator is Aaron"
})
ChemListChem 将会引用 Chem 以及 ChemList 两个 Collection
const mongoose = require('mongoose');
const {
Schema
} = mongoose;
const chemListChemSchema = new mongoose.Schema({
chemical: {
type: Schema.Types.ObjectId,
ref: 'Chem'
},
list: {
type: Schema.Types.ObjectId,
ref: 'ChemList'
},
maxValue: Number,
minValue: Number,
active: Boolean,
});
module.exports = mongoose.model('ChemListChem', chemListChemSchema);
searchChemListChem: (root, {
list
}) => ChemListChem.find({
list: new ObjectId(list)
// 这个地方很重要,必须生成一个 Object ID
}).populate('list').then((res) => {
// 然后使用 populate 来获取引用的数据
console.log(res);
}),
Schema.Types.ObjectId
可以根据需要改成其他的类型,但是不推荐ObjectID("xxx")
populate()
之前应该返回一个 ID, 使用 populate() 之后应该返回一个 Object