所以我在我的JavaScript应用程序上使用Sequelize作为我的PostgreSQL数据库。我有4个模型(用户,帖子,喜欢和关注跟随者)。我的用户模型工作正常,它没有任何外键,所以我能够创建和查找数据没有任何问题。但是,我的Posts模型有2个外键(user_id和parent_id)。 user_id引用Users表中的主键(id),parent_id引用自身的主键(id)(Posts表)。当我尝试将数据插入Posts表时,我能够在常规字段上插入数据,但外键只是被忽略。
这是我的数据库连接:
const Sequelize = require('sequelize');
const API = require('../../client/public/config.js');
const db = new Sequelize(API.elephantSqlUrl);
db.authenticate()
.then(() => {
console.log('Connection has been established successfully.');
})
.catch((err) => {
console.error('Unable to connect to the database:', err);
});
module.exports = db;
这是我的用户模型:
const Sequelize = require('sequelize');
const db = require('../db.js');
const Users = db.define('users', {
username: {
type: Sequelize.STRING,
unique: true
},
bio: Sequelize.STRING,
profile_picture: Sequelize.STRING
});
module.exports = Users;
这是我的帖子模型:
const Sequelize = require('sequelize');
const db = require('../db.js');
const Posts = db.define('posts', {
type: Sequelize.INTEGER,
body: Sequelize.STRING,
likesCount: {
type: Sequelize.INTEGER,
defaultValue: 0
}
});
module.exports = Posts;
这是我定义外键和同步我的数据库的地方:
const db = require('./db.js');
const Users = require('./models/users.js');
const Posts = require('./models/posts.js');
const Likes = require('./models/likes.js');
const FollowingsFollowers = require('./models/followingsFollowers.js');
Posts.belongsTo(Users, { foreignKey: 'user_id' });
Users.hasMany(Posts, { foreignKey: 'user_id' });
Posts.belongsTo(Posts, { foreignKey: 'parent_id' });
Posts.hasMany(Posts, { foreignKey: 'parent_id' });
Likes.belongsTo(Posts, { foreignKey: 'post_id' });
Posts.hasMany(Likes, { foreignKey: 'post_id' });
Likes.belongsTo(Users, { foreignKey: 'user_id' });
Users.hasMany(Likes, { foreignKey: 'user_id' });
FollowingsFollowers.belongsTo(Users, { foreignKey: 'following_id' });
Users.hasMany(FollowingsFollowers, { foreignKey: 'following_id' });
FollowingsFollowers.belongsTo(Users, { foreignKey: 'follower_id' });
Users.hasMany(FollowingsFollowers, { foreignKey: 'follower_id' });
db.sync({ force: true })
.then(() => {
console.log('db synced');
})
.catch(() => {
console.log('error syncing db');
});
这是我尝试添加帖子的地方:
const addPost = (username, post) => {
return new Promise((resolve, reject) => {
Users.findOne({ where: { username: username } })
.then((user) => {
post.user_id = user.id;
Posts.create()
.then((created) => {
resolve();
});
})
.catch((err) => {
reject(err);
});
});
};
当我使用用户名和带有“type”和“body”键的对象调用此函数时,会创建一个Post。但是,Post包含“id”,“type”,“body”,“likesCount”,“createdAt”和“updatedAt”字段。 “user_id”字段永远不会添加到那里。
我不知道这是否会解决您的问题,但您没有将任何参数传递给create()
方法。 post
对象被传递给函数,富含user_id
和...被忽略。
不应该这样吗?:
(...)
Posts.create(post)
(...)
我能够解决它。我的解决方案是在我的模型文件上添加外键关系,如下所示:
const Sequelize = require('sequelize');
const Users = require('./users.js');
const db = require('../db.js');
const Posts = db.define('posts', {
type: Sequelize.INTEGER,
body: Sequelize.STRING,
likesCount: {
type: Sequelize.INTEGER,
defaultValue: 0
}
});
Posts.belongsTo(Users, { foreignKey: 'user_id' });
Posts.belongsTo(Posts, { foreignKey: 'parent_id' });
module.exports = Posts;
然后对于我同步我的数据库的文件,那就是我会做的,就像这样:
const db = require('./db.js');
const Users = require('./models/users.js');
const Posts = require('./models/posts.js');
const Likes = require('./models/likes.js');
const FollowingsFollowers = require('./models/followingsfollowers.js');
db.sync({ force: true })
.then(() => {
console.log('db synced');
})
.catch(() => {
console.log('error syncing db');
});