大家好，我目前正在一个laravel项目中工作，我有一个父表，有三个表的id引用它。这些表迁移也有各自的模型。下面分别是表迁移文件:
create_products_table.php
Schema::create('products', function (Blueprint $table) {
$table->id();
$table->string('product_id', 10);
$table->string('product_name');
$table->string('image');
$table->string('images');
$table->string('product_description');
$table->bigInteger('size_id')->unsigned();
$table->string('color');
$table->string('product_quantity');
$table->string('old_price');
$table->string('discount');
$table->string('product_price');
$table->bigInteger('user_id')->unsigned()->nullable();
$table->bigInteger('category_id')->unsigned();
$table->bigInteger('gender_id')->unsigned();
$table->timestamps();
$table->foreign('size_id')->references('id')->on('sizes')->onDelete('cascade');
$table->foreign('category_id')->references('id')->on('categories')->onDelete('cascade');
$table->foreign('gender_id')->references('id')->on('genders')->onDelete('cascade');
});
create_genders_table.php
Schema::create('genders', function (Blueprint $table) {
$table->id();
$table->string('gender_class');
$table->timestamps();
});
create_categories_table.php
Schema::create('categories', function (Blueprint $table) {
$table->id();
$table->string('cat_name');
$table->timestamps();
});
create_sizes_table.php
Schema::create('sizes', function (Blueprint $table) {
$table->id();
$table->string('sizes');
$table->timestamps();
});
这也是我如何分别定义它们模型上的关系
Product.php
public function category()
{
return $this->belongsTo(Category::class);
}
public function gender()
{
return $this->belongsTo(Gender::class);
}
public function size()
{
return $this->belongsTo(Size::class);
}
Category.php
public function products()
{
return $this->hasMany(Product::class);
}
Gender.php
public function products()
{
return $this->hasMany(Product::class);
}
Size.php
public function products()
{
return $this->hasMany(Product::class);
}
我实际上是一个laravel.com的初学者，我在laravel.com上学习了雄辩的模型关系，所以我所做的只是基于我对一对多关系的理解。当我用dd($request)检查我的所有请求时，category_id, gender_id, size_id都显示为空，我相信这是因为我没有正确定义关系。现在我非常需要你的帮助。
所以请我的经验丰富的开发人员，我真的需要你的帮助，我真的很感激，如果我今天得到你的答复。提前谢谢。
=>Everything is right, just make changes in the products migration add this code.
$table->foreign('size_id')->references('id')->on('products')->onDelete('cascade');
$table->foreign('category_id')->references('id')->on('products')->onDelete('cascade');
$table->foreign('gender_id')->references('id')->on('products')->onDelete('cascade');
=>and migrate table