Laravel6中多表关系的检索结果

// User模型
class User extends Model
{
    public function card()
    {
        return $this->hasOne(Card::class);
    }
}

// Card模型
class Card extends Model
{
    public function user()
    {
        return $this->belongsTo(User::class);
    }
}

// 查询用户及其身份证信息
$user = User::with('card')->find(1);

// User模型
class User extends Model
{
    public function articles()
    {
        return $this->hasMany(Article::class);
    }
}

// Article模型
class Article extends Model
{
    public function user()
    {
        return $this->belongsTo(User::class);
    }
}

// 查询用户及其所有文章
$user = User::with('articles')->find(1);

// Article模型
class Article extends Model
{
    public function tags()
    {
        return $this->belongsToMany(Tag::class);
    }
}

// Tag模型
class Tag extends Model
{
    public function articles()
    {
        return $this->belongsToMany(Article::class);
    }
}

// 查询文章及其所属标签
$article = Article::with('tags')->find(1);