php - 我们如何在laravel中使用外键将数据从一个表插入到另一个表？

Question

假设我有一个表(“附件”)，另一个是表(“品牌”)。我想从品牌表中附加一个品牌标识，它将保存到表(“附件”)中。我是初学者提前抱歉。请帮我。\这是我的品牌 Controller ......

 public function create()
{
    $brands = Brand::all();
    $catagories = Catagory::all();
    $attachments = Attachment::all();
    return view('system-mgmt/brand/create', ['brands' => $brands, 'catagories' => $catagories,'attachments'=>  $attachments]);

}

/**
 * Store a newly created resource in storage.
 *
 * @param  \Illuminate\Http\Request  $request
 * @return \Illuminate\Http\Response
 */
public function store(Request $request)
{
    Catagory::findOrFail($request['catID']);
    Attachment::findOrFail($request['attachmentID']);
    $this->validateInput($request);
     Brand::create([
        'brandsName' => $request['brandsName'],
        'attachmentID' => $request['attachmentID'],
        'catID' => $request['catID']
    ]);

    return redirect()->intended('system-management/brand');
}

这是我的 html 代码，这段代码是从附件表中获取数据...但我的要求是“数据将由用户插入”

 <div class="form-group">
                        <label class="col-md-4 control-label">Brand Logo</label>
                        <div class="col-md-6">
                            <select class="form-control" name="attachmentID">
                                @foreach ($attachments as $attachment)
                                    <option value="{{$attachment->id}}">{{$attachment->attachmentName}}</option>
                                @endforeach
                            </select>
                        </div>
                    </div>

Answer 1

您想将一个表的数据插入另一个关系表不是最佳做法。
在这里你可以使用 join选择数据时查询并避免插入过程更好。

将 brands 表与 attachments 表连接起来，并在 外键 之后访问 brand_logo。

//Please make sure your table and field name is correct   
$attachments = DB::table('attachments')
                ->leftJoin('brands', 'attachments.id', '=', 'brands.attachmentID')
                ->select('attachments.*','brands.brand_logo')
                ->first();

echo $attachments->brand_logo;

However some time need to copy on table data to others table in this purpose you can do this.

//Laravel DB raw insert query
\DB::insert("INSERT INTO table_a(fld_a,fld_b)
    SELECT
        fld_a,fld_b // Make sure select column same sequence of insert field name(fld_a,fld_b).
    FROM
        table_b
    WHERE table_b.id > 100  //condition
        ");

详情 here .