如果子关系在 Laravel 中有结果，我如何只返回父级，如果关系是三重嵌套的？

Posted 2023-02-16

【中文标题】如果子关系在 Laravel 中有结果，我如何只返回父级，如果关系是三重嵌套的？

【英文标题】：How do I only return the parent if child has results in Laravel, if the relations are triple nested?

【发布时间】：2021-05-13 07:47:35

【问题描述】：

我有以下关系Client > belongsToMany Brand > hasMany Handles > hasMany Content.

如果Content 有行，我将如何只返回Handles，如果Handles 有行，则只返回Brands，如果它也有行，则只返回Client，我从PostgreSQL 数据库中获取？

这是模型的刮版

客户端模型

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsToMany;
use Illuminate\Database\Eloquent\SoftDeletes;

class Client extends Model

    use HasFactory;
    use SoftDeletes;

    protected $hidden = ['pivot'];

    protected $fillable = ['title', 'subscription_expire', 'subscription_level'];


    /**
     * Get brands for client
     *
     * @return BelongsToMany
     */
    public function brands(): BelongsToMany
    
        return $this->belongsToMany(
            Brand::class,
            'organized_objects',
            'client_id',
            'object_id'
        )->wherePivot('object_type', 'brand');
    

品牌模型

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\SoftDeletes;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Relations\BelongsToMany;

class Brand extends Model

    use HasFactory;
    use SoftDeletes;

    /**
     * Get handles for brand
     *
     * @return BelongsToMany
     */
    public function handles(): BelongsToMany
    
        return $this->belongsToMany(Handle::class, 'handle_pivots', 'handle_pivot_id', 'handle_id');
    

手柄模型

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\Factories\HasFactory;

class Handle extends Model

    use HasFactory;

    protected $fillable = ['name', 'platform'];

    /**
     * Get content of handle.
     *
     * @return HasMany
     */
    public function content(): HasMany
    
        return $this->hasMany(PureContent::class, 'handle_id');
    

目前，我在控制器中执行以下操作以获取句柄所需的内容。

/**
 * Client metrics
 *
 * Displays metrics for the given client
 *
 * @param Request $request
 * @param Client  $client
 *
 * @return JsonResponse
 */
public function index(Request $request, Client $client): JsonResponse

    $to = $request->get('to');
    $from = $request->get('from');
    $to_date = $to ? Carbon::parse($to) : Carbon::now();
    $from_date = $from ? Carbon::parse($from) : $to_date->copy()->startOfYear();

    $client_content = $client->with([
        'brands' => function ($q) use ($to_date, $from_date) 
            $q->with([
                'handles' => function ($q) use ($to_date, $from_date) 
                    $q->whereHas('content', function ($q) use ($to_date, $from_date) 
                        $q->whereBetween('created_at', [$from_date, $to_date]);
                    )->with(['content' => function ($q) use ($to_date, $from_date) 
                        $q->whereBetween('created_at', [$from_date, $to_date]);
                    ])->get();
                ,
            ])->get();
        ,
    ])->get();

    return response()->json($client_content);

但是当我返回集合时，我仍然得到相关的集合只是空的。

例如，在查询中添加一个 Collection 模型需要多少费用？它与品牌 > 处理 > 内容的设置相同？

【问题讨论】：

不应该更像$client->with(['brands'])->whereHas('handles', function ($query) $query->whereBetween....

@C4pt4inC4nn4bis 不，只是查询Client::handles();

也许这有帮助webdevetc.com/programming-tricks/laravel/laravel-eloquent/…

【参考方案1】：

我相信您的主查询中还需要嵌套 whereHas 子句来过滤不相关的客户记录

$client_content=$client->with(.....)
                       ->whereHas('brands', function (Builder $query) use ($to_date, $from_date) 
                            $query->whereHas('handles', function (Builder $query) use ($to_date, $from_date) 
                                $query->whereHas('content', function (Builder $query) use ($to_date, $from_date) 
                                    $query->whereBetween('created_at', [$from_date, $to_date]);
                                );
                            );
                        )->get();

现在您只是从 with() 部分过滤关联的记录，但您还需要在主查询中使用此过滤器来删除具有空集合的此类记录