laravel 已用于生产环境的表添加字段的方法

art make:migration  add _user_id_collum_to_Projects_table  --table=projects

public function up()
    {
        Schema::table(‘projects‘, function (Blueprint $table) {
            //
            $table->integer(‘user_id‘);
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::table(‘projects‘, function (Blueprint $table) {
            //
            $table->dropColumn(‘user_id‘);
        });
    }