Laravel 使用关系过滤查询结果

Question

I have this relations 并为所有 3 个表定义了模型

class Employee extends Model
{
    use HasFactory;
    protected $table = 'employees';
    public function departments()
    {
        return $this->belongsToMany(Department::class, 'dept_emp', 'emp_no', 'dept_no', 'emp_no', 'dept_no');
    }
}
class Department extends Model
{
    use HasFactory;
    protected $table = 'departments';

}
class Dept_emp extends Model
{
    use HasFactory;
    protected $table = 'dept_emp';
}

在我的控制器中

 $employees = Employee::with('departments')->paginate(50);

我想过滤这个查询结果，以便能够只选择一个选定的部门，而不是全部。

我尝试将此功能添加到员工模型中

    public function scopeDepartment($query, $department)
    {
        return $query->where('dept_no',$department);
    }

但它不起作用。有人可以建议我如何使用关系过滤查询结果吗？

Answer 1

你可以像这样在关系中查询

$employees = Employee::with(['departments' => function($q) use ($dept_id){
  $q->where('dept_no',$dept_id);
}])->paginate(50);

$dept_id 是部门的 ID，即 $dept_id = $request->department_id 类似