BelongsToMany 关系 - 续集

Question

我在使用 sequelize + nodejs 列出具有 belongsToMany 关联的记录时遇到问题。

我有开发人员和技术table。他们之间的关系是多对多的。要创建关系，请使用名为 developers_technologies.

的枢轴 table

以下是代码要点：模型（开发人员、技术）、迁移（developers_technologies）和开发人员的控制器。

https://gist.github.com/fredarend/85ff60fca70643d80301b499e871c4a6

controller Developer的Index代码是这样的：

async index(req, res) {
const developers = await Developer.findAll({
  attributes: ['id', 'name', 'email'],
  include: [
    {
      model: Technologies,
      as: 'technologies',
      attributes: ['id', 'name'],
      through: { attributes: [] },
    },
  ],
});

return res.json(developers);}

Return:

[
    {
        "id": 25,
        "name": "Jon Doe",
        "email": "jondoe@gmail.com",
        "age": 27,
        "url_linkedin": "http://asdasdasd",
        "technologies": []
    }
]

我想知道为什么我没有收到与开发人员相关的技术，因为数据库中的 developers_technologies table 已填充并且模型中的关系正常。

编辑：从请求生成的查询：

SELECT 
"Developer"."id", 
"Developer"."name", 
"Developer"."email", 
"technologies"."id" AS "technologies.id", 
"technologies"."name" AS "technologies.name", 
"technologies->developers_technologies"."created_at" AS "technologies.developers_technologies.createdAt", 
"technologies->developers_technologies"."updated_at" AS "technologies.developers_technologies.updatedAt", 
"technologies->developers_technologies"."developer_id" AS "technologies.developers_technologies.developer_id", 
"technologies->developers_technologies"."technology_id" AS "technologies.developers_technologies.technology_id" 
FROM "developers" AS "Developer" 
LEFT OUTER JOIN ( "developers_technologies" AS "technologies->developers_technologies" 
INNER JOIN "technologies" AS "technologies" ON "technologies"."id" = "technologies->developers_technologies"."developer_id") ON "Developer"."id" = "technologies->developers_technologies"."technology_id";

亲切的问候，

Answer 1

尝试在 belongToMany 关联中指出 otherKey。您还指出了错误的外键。对于 Developer，它应该是 developer_id，对于 Technology，它应该是 technology_id:

模型 - 开发者

this.belongsToMany(models.Technology, {
      foreignKey: 'developer_id',
      otherKey: 'technology_id',
      through: 'developers_technologies',
      as: 'technologies',
    });

模型 - 技术

this.belongsToMany(models.Developer, {
      foreignKey: 'technology_id',
      otherKey: 'developer_id',
      through: 'developers_technologies',
      as: 'developers',
    });

BelongsToMany 关系 - 续集

BelongsToMany Relationship - Sequelize

api

rest

node.js

express

sequelize.js