我试图迁移我的Rails MySQL数据库，我收到以下错误：

ActiveRecord :: StatementInvalid：Mysql2 :: Error：无法创建表development.comments(错误：150“外键约束形成错误”)：CREATE TABLE注释(id int AUTO_INCREMENT PRIMARY KEY，comment varchar(255)，user_id int，post_id int，created_at datetime NOT NULL，updated_at datetime NOT NULL，INDEX index_comments_on_user_id(user_id)，INDEX index_comments_on_post_id(post_id)，CONSTRAINT fk_rails_03de2dc08c FOREIGN KEY(user_id)REFERENCES users(id)，CONSTRAINT fk_rails_2fd19c0db7 FOREIGN KEY(post_id)REFERENCES posts( id))ENGINE = InnoDB

以下是我的迁移：

class CreateUsers < ActiveRecord::Migration[5.0]

def change

create_table :users do |t|

t.string :first_name

t.string :last_name

t.string :linkedin_username

t.string :facebook_username

t.string :facebook_id

t.string :profile_image

t.string :title_image

t.string :connection

t.boolean :team

t.boolean :active

t.boolean :admin

t.string :email

t.string :password_digest

t.timestamps

end

end

end

class CreateComments < ActiveRecord::Migration[5.0]

def change

create_table :comments do |t|

t.string :comment

t.references :user, foreign_key: true

t.references :post, foreign_key: true

t.timestamps

end

end

end

class CreateCategories < ActiveRecord::Migration[5.0]

def change

create_table :categories do |t|

t.string :name

t.text :description

t.timestamps null: false

end

end

end

class CreatePosts < ActiveRecord::Migration[5.0]

def change

create_table :posts do |t|

t.string :title

t.string :description

t.references :category, foreign_key: true

t.references :user, foreign_key: true

end

end

end

如果有人能在这里给我一个想法，我将非常感激 . 我一直在谷歌搜索解决方案一段时间，但无法找到与Rails相关的任何内容 . 谢谢！