BelongsToMany 急切加载为每个关联返回多个对象

Question

I have two models: User and EconomicActivity. They are associated through UserEconomicActivity (it's a BelongsToMany relation). In User model, I have defined the association like this:

this.belongsToMany(models.EconomicActivity, {
  through: 'UserEconomicActivity',
  as: 'economicActivities',
  otherKey: {
    name: 'economicActivityId',
    allowNull: false
  },
  foreignKey: {
    name: 'userId',
    allowNull: false
  }
})

I'm trying to query User where it is associated with one or more EconomicActivity, like this:

const users = await User.findAll({
  include: [
    {
      model: EconomicActivity,
      as: 'economicActivities',
      where: {
        id: filters.economicActivities // This is an array with IDs I want to filter
      }
    }
  ],
  raw: true,
  nest: true
})

Let's say that one specific User is associated to 2 EconomicActivity. When I run this query, it returns the same user two times, one for each association. I want to return the same user just one time with an array of associated economicActivities inside it (like user.economicActivities). Is this possible?

Answer 1

By setting raw to true, you're explicitly asking for this result format. I also don't see the use of nest here.

I suggest you remove both parameters.

See the Sequelize API Reference for more info.

Answer 2

As I said in a comment, I needed to use raw and nest because I'm passing the data to Handlebars, and Handlebars can only output plain JavaScript objects, otherwise it gives me the error Handlebars: Access has been denied to resolve the property "name" because it is not an "own property" of its parent and will not output the data.

But, I found a way to get a plain JavaScript object and also keeping all the associations inside an array:

await this.model.findAll(query).map(item => item.get({ plain: true }))

The model's get method does exactly what I want. Because I'm using findAll , I use ES6 map method to call get from every model returned from the query.