Using sequelize and mySQL, I have two tables: User and Post.

The relationship between the two tables is M:N

db.User.belongsToMany(db.Post, { through: "Likes", as: "Liked" }); db.Post.belongsToMany(db.User, { through: "Likes", as: "Likers" });

What I want is to get all the liker ids and the number of likers of the post.

I know you can get all likers like this.

const post = await Post.findOne({ where: { id: postId }, attributes: ["id", "title", "imageUrl"], include: [{ model: User, as: "Likers", attributes: ["id"], through: { attributes: [] }, }] }) // result { "id": 36, "title": "test", "imageUrl": "하늘이_1644886996449.jpg", "Likers": [ { "id": 13 }, { "id": 16 } ] }

Also, I also know that I can get the number of likes this way.

const post = await Post.findOne({ where: { id: postId }, attributes: ["id", "title", "imageUrl"], include: [{ model: User, as: "Likers", attributes: [[sequelize.fn("COUNT", "id"), "likersCount"]], }] }) // result { "id": 36, "title": "test", "imageUrl": "하늘이_1644886996449.jpg", "Likers": [ { "likersCount": 2 } ] }

However, I don't know how to get both of them at the same time. Check the results when I use them both.

{ model: User, as: "Likers", attributes: ["id", [sequelize.fn("COUNT", "id"), "likersCount"]], through: { attributes: [] }, } // result "Likers": [ { "id": 13, "likersCount": 2 } ]

It only shows one liker (id: 13) It should show another liker (id: 16).

What is the problem?