Question

当我编译我的节点应用程序试图在模型类中放置许多关系时，会出现此错误

MyModel.hasMany called with something that's not a subclass of Sequelize.Model

这是我的模型类 Poll.js ：

import Sequelize from 'sequelize'
import { sequelize } from '../database/database'
import Catchment from './Catchment'
import Question from './Question'

const Poll = sequelize.define('polls', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true
    },
    title: {
        type: Sequelize.TEXT
    },
    enabled: {
        type: Sequelize.BOOLEAN
    },
    created_at: {
        type: 'TIMESTAMP'
    },
    updated_at: {
        type: 'TIMESTAMP'
    }
},{
    timestamps: false
})

Poll.hasMany(Question, { foreignKey: { name:'poll_id', unique: false}, as: 'questions' })
Poll.hasMany(Catchment, { foreignKey: { name:'poll_id', unique: false}, as: 'catchments' })

export default Poll

Question.js

import Sequelize from 'sequelize'
import { sequelize } from '../database/database'
import Poll from './Poll';

const Question = sequelize.define('questions', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true
    },
    poll_id: {
        type: Sequelize.INTEGER
    },
    title: {
        type: Sequelize.TEXT
    },
    created_at: {
        type: 'TIMESTAMP'
    },
    updated_at: {
        type: 'TIMESTAMP'
    }
},{
    timestamps: false
})

Question.belongsTo(Poll, { foreignKey: { name:'poll_id', unique: false}, as: 'poll' })

export default Question

Catchment.js

import Sequelize from 'sequelize'
import { sequelize } from '../database/database'
import Poll from './Poll'

const Catchment = sequelize.define('catchments', {
    id: {
        type: Sequelize.INTEGER,
        primaryKey: true
    },
    poll_id: {
        type: Sequelize.INTEGER
    },
    created_at: {
        type: 'TIMESTAMP'
    },
    updated_at: {
        type: 'TIMESTAMP'
    }
}, {
    timestamps: false
})

Catchment.belongsTo(Poll, { foreignKey: { name: 'poll_id', unique: false }, as: 'poll' })

export default Catchment

架构为：

民意调查（有很多）->问题
民意调查（很多）->集水区

我认为可能是因为它们具有相同的ForeignKey名称：poll_id，谢谢

Answer 1

我认为问题在于模块之间的循环依赖关系。显然，您是按顺序要求它们的，而相关模型并不能全部那样提供。

定义模型并不导出关联，然后在定义模型后创建关联。

例如：

// create the model definitions
const User = require('./user');
const Department = require('./department');

// now that you have the model definitions, create the associations
User.belongsTo(Department, {foreignKey: 'department_id'});
Department.hasMany(User, {foreignKey: 'department_id'});

// or like the below as the models should now exist on sequelize.models
sequelize.models.user.belongsTo(sequelize.models.department, {foreignKey: 'department_id'});
sequelize.models.department.hasMany(sequelize.models.user, {foreignKey: 'department_id'});

Sequelize-错误许多具有相同名称的关系ForeignKey-MyModel.hasMany调用的不是Sequelize.Model的子类

1 个答案: