如何从连接表中选择列:laravel eloquent [英] How to select columns from joined tables: laravel eloquent

问题描述

我有一个与 这个不同的问题.场景相同，但我需要对结果进行更多过滤.

I have a different problem from this. The scenario is same but I am in need of more filtration of the results.

让我解释一下.

考虑我有 2 张桌子

车辆

 id
 name
 staff_id
 distance
 mileage

员工

 id
 name
 designation

我只想从两个表(模型)中选择 id 和 name.Vehicle Model 包含与 Staff 模型的 belongsTo 关系.

I want to select only id and name from both tables(Models). The Vehicle Model contain a belongsTo relation to Staff model.

class Vehicle extends Model
{
    public function staff()
    {
      return $this->belongsTo('AppStaff','staff_id');
    }
}

我加入使用这个

Vehicle::where('id',1)
            ->with(['staff'=> function($query){
                            // selecting fields from staff table
                            $query->select(['staff.id','staff.name']);
                          }])
            ->get();

当我像这样将字段放在 ->get() 中时

When I put fields in ->get() like this

->get(['id','name'])

它过滤了vehicle表，但没有产生Staff表的结果.

it filters the vehicle table but produce no result of Staff table.

有什么想法吗?

推荐答案

终于找到了..在 ->get() 中，你必须像这样输入 'staff_id'

Finally found it.. In the ->get() you have to put the 'staff_id' like this

Vehicle::where('id',1)
            ->with(['staff'=> function($query){
                            // selecting fields from staff table
                            $query->select(['staff.id','staff.name']);
                          }])
            ->get(['id','name','staff_id']);

由于我没有使用 staff_id，它无法执行连接，因此没有显示人员表字段.

Since I didn't take the staff_id, it couldn't perform the join and hence staff table fields were not shown.

这篇关于如何从连接表中选择列:laravel eloquent的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！