errno: 150 “外键约束的格式不正确”？

Question

我正在尝试创建标签和文章之间的关系表，但遇到了问题。

迁移代码：

 Schema::create('article_tag', function (Blueprint $table) {
        $table->id();
        $table->unsignedBigInteger('article_id');
        $table->unsignedBigInteger('tag_id');
        $table->timestamps();



        $table->foreign('article_id')->references('id')->on('articles')->onDelete('cascade'); 
        $table->foreign('tag_id')->references('id')->on('tags')->onDelete('cascade');
      });

错误： SQLSTATE[HY000]: General error: 1005 Can't create table hiro_blog.article_tag (errno: 150 "Foreign key constraint is wronglyformed") (SQL: alter table article_tag add constraint article_tag_article_id_foreign 外键 (article_id) 在删除级联上引用 articles (id)