Laravel - 如何将外键引用添加到已经存在的迁移

Question

在我的 Larave-8 中，我使用此迁移创建了一个表：

public function up()
{
    Schema::create('profiles', function (Blueprint $table) {
        $table->bigIncrements('id');
        $table->bigInteger('user_id');
        $table->string('first_name',50);
        $table->string('last_name',50);
        $table->string('other_name',50)->nullable();
        $table->string('gender',20);
        $table->string('user_photo',350)->nullable();
        $table->integer('nationality_id');
        $table->string('marital_status',50);
        $table->date('dob')->nullable();
        $table->string('address', 300)->nullable();
        $table->integer('country_id')->nullable();
        $table->integer('state_id')->nullable();
        $table->integer('city_id')->nullable();
        $table->string('cv_file',350)->nullable();
        $table->text('summary')->nullable();
        $table->timestamps();

        $table->foreign('user_id')->references('id')->on('users');
    });
}

如何通过迁移更改表并添加这些：

        $table->foreign('nationality_id')->references('id')->on('countries');
        $table->foreign('country_id')->references('id')->on('countries');
        $table->foreign('state_id')->references('id')->on('state_origins');
        $table->foreign('city_id')->references('id')->on('cities');

谢谢

Answer 1

创建另一个迁移，例如更改现有表

public function up()
    {
        Schema::table('profiles', function (Blueprint $table) {
            $table->foreign('nationality_id')->references('id')->on('countries');
            $table->foreign('country_id')->references('id')->on('countries');
            $table->foreign('state_id')->references('id')->on('state_origins');
            $table->foreign('city_id')->references('id')->on('cities');
        });
    }

    public function down() {
        Schema::table('profiles', function (Blueprint $table) {
            $table->dropForeign('nationality_id');
            $table->dropForeign('country_id');
            $table->dropForeign('state_id');
            $table->dropForeign('city_id');
        });
    }