Sequelize errno: 150 "Foreign key constraint is incorrectly formed"

Question

I have a problem with migrating two tables with relationships. I want to add a foreign key to product.js migration, but it is not working. If I will run the application with await sequelize.sync(); database creating well.

How to fix this issue? I did the same thing with another migrations user and addresses, and it worked as I expected. Appreciate your help.

== 20210124144301-create-product: migrating =======

ERROR: Can't create table database_development.products (errno: 150 "Foreign key constraint is incorrectly formed")

create-category.js migration:

"use strict";
module.exports = {
  up: async (queryInterface, Sequelize) => {
    await queryInterface.createTable("сategories", {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER,
      },
      name: {
        type: Sequelize.STRING,
        allowNull: false,
        unique: true,
      },
      description: Sequelize.TEXT,
      createdAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
      updatedAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
    });
  },
  down: async (queryInterface, Sequelize) => {
    await queryInterface.dropTable("сategories");
  },
};

create-product.js migration:

"use strict";
module.exports = {
  up: async (queryInterface, Sequelize) => {
    await queryInterface.createTable("products", {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER,
      },
      categoryId: {
        type: Sequelize.INTEGER,
        allowNull: false,
        references: {
          model: "categories",
          key: "id",
        },
      },
      name: {
        type: Sequelize.STRING,
        allowNull: false,
      },
      description: {
        type: Sequelize.TEXT,
        allowNull: false,
      },
      price: {
        type: Sequelize.DOUBLE(11, 2).UNSIGNED,
        defaultValue: 0,
      },
      createdAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
      updatedAt: {
        allowNull: false,
        type: Sequelize.DATE,
      },
    });
  },
  down: async (queryInterface, Sequelize) => {
    await queryInterface.dropTable("products");
  },
};

category.js model:

"use strict";
const { Model } = require("sequelize");
module.exports = (sequelize, DataTypes) => {
  class Category extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      this.hasMany(models.Product, {
        foreignKey: "categoryId",
      });
    }
  }
  Category.init(
    {
      name: {
        type: DataTypes.STRING,
        allowNull: false,
        unique: true,
      },
      description: DataTypes.TEXT,
    },
    {
      sequelize,
      tableName: "categories",
      modelName: "Category",
    }
  );
  return Category;
};

product.js model:

"use strict";
const { Model } = require("sequelize");
module.exports = (sequelize, DataTypes) => {
  class Product extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      this.belongsTo(models.Category, {
        foreignKey: "categoryId",
      });
    }
  }
  Product.init(
    {
      name: {
        type: DataTypes.STRING,
        allowNull: false,
      },
      description: {
        type: DataTypes.TEXT,
        allowNull: false,
      },
      price: {
        type: DataTypes.DOUBLE(11, 2).UNSIGNED,
        defaultValue: 0,
      },
    },
    {
      sequelize,
      tableName: "products",
      modelName: "Product",
    }
  );
  return Product;
};

Answer 1

the foreign key must be the same type of the primary key on the other table

Answer 2

You need to add primary key(id) in your product and category model file also change your model associations .

product.js

 "use strict";
const { Model } = require("sequelize");
module.exports = (sequelize, DataTypes) => {
  class Product extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      Product.belongsTo(models.Category, {
        foreignKey: "categoryId",
      });
    }
  }
  Product.init(
    {
      productId: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: DataTypes.INTEGER
      },
      name: {
        type: DataTypes.STRING,
        allowNull: false,
      },
      description: {
        type: DataTypes.TEXT,
        allowNull: false,
      },
      price: {
        type: DataTypes.DOUBLE(11, 2).UNSIGNED,
        defaultValue: 0,
      },
      categoryId: {
        type: DataTypes.INTEGER
      }
    },
    {
      sequelize,
      tableName: "products",
      modelName: "Product",
    }
  );
  return Product;
};

Category.js

"use strict";
const { Model } = require("sequelize");
module.exports = (sequelize, DataTypes) => {
  class Category extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      Category.hasMany(models.Product, {
        foreignKey: "categoryId",
      });
    }
  }
  Category.init(
    {
      categoryId: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: DataTypes.INTEGER
      },
      name: {
        type: DataTypes.STRING,
        allowNull: false,
        unique: true,
      },
      description: DataTypes.TEXT,
    },
    {
      sequelize,
      tableName: "categories",
      modelName: "Category",
    }
  );
  return Category;
};