Sequelize 不创建模型关联列 [英] Sequelize not creating model association columns

问题描述

我对 Sequelize 何时为关联创建字段感到有些困惑.

I'm a little confused with when Sequelize creates the fields for associations.

我已经使用 sequelize-cli 创建了我的迁移.这生成了一个迁移和模型文件.然后在模型文件中我填充了我的关联.然后运行 ​​npx sequelize-cli db:migrate.

I've created my migrations using sequelize-cli. This generated a migration and model file. Then in the model file I populated my associations. Then ran npx sequelize-cli db:migrate.

这会创建表，但不会创建模型中定义的关联所需的外键.

This creates the tables but not the foreign keys needed for the associations defined in the model.

例如:迁移问题:

"use strict";
module.exports = {
  up: (queryInterface, Sequelize) => {
    return queryInterface.createTable("questions", {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER
      },
      category: {
        type: Sequelize.INTEGER
      },
      question: {
        type: Sequelize.STRING
      },
      createdAt: {
        allowNull: false,
        defaultValue: new Date(),
        type: Sequelize.DATE
      },
      updatedAt: {
        allowNull: false,
        defaultValue: new Date(),
        type: Sequelize.DATE
      }
    });
  },
  down: (queryInterface, Sequelize) => {
    return queryInterface.dropTable("questions");
  }
};

模型问题:

"use strict";
module.exports = (sequelize, DataTypes) => {
  const questions = sequelize.define(
    "questions",
    {
      question: DataTypes.STRING,
      weight: DateTypes.INTEGER
    },
    {}
  );
  questions.associate = function(models) {
    // associations can be defined here
    models.questions.hasOne(models.question_categories);
    models.questions.hasMany(models.question_answers);
  };
  return questions;
};

推荐答案

需要提供外键使用的列.这些线路上的东西

You need to provide the columns which are used in the foreign key. Something on these lines

  questions.associate = function(models) {
    // associations can be defined here
    models.questions.hasOne(models.question_categories, { foreignKey: 'question_id' });
    models.questions.hasMany(models.question_answers, { foreignKey: 'question_id' });
  };

这将在表 question_categories 中创建一个外键，指向表 questions

This will create a foreign key in table question_categories, pointing to the table questions

question_categories.question_id -> questions.id

这篇关于Sequelize 不创建模型关联列的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！