php - 在 Laravel 5 中将 `dateTime` 列拆分为单独的 `date` 和 `time` 列

Question

我有一个名为“offers”的表，其中有一列名为 start_date，类型为 dateTime。

我想将此列拆分为两个单独的列:

• start_date 类型 date
• start_time 类型 time

为此，我有以下代码:

<?php

use App\Offer;
use Carbon\Carbon;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class FixOffersTable extends Migration
{
    public function up()
    {
        Schema::table('offers', function(Blueprint $table)
        {
            $table->renameColumn('start_date', 'start_date_time');
            $table->renameColumn('end_date', 'end_date_time');
        });

        Schema::table('offers', function (Blueprint $table)
        {
            $table->date('start_date')->after('start_date_time')->nullable();
            $table->time('start_time')->after('start_date')->nullable();

            foreach (Offer::all() as $offer) {
                /* Cannot use model mutator, as model class can change over time, and may no longer have certain columns
                in the $casts attribute. Therefore using the raw string fetched from the MySQL database. */
                $startDateTime = Carbon::createFromFormat('Y-m-d H:i:s', $offer->getOriginal('start_date_time'));
                $offer->start_date = Carbon::createFromDate($startDateTime->year, $startDateTime->month, $startDateTime->day);
                $offer->start_time = Carbon::createFromTime($startDateTime->hour, $startDateTime->minute, $startDateTime->second);
                $offer->save();
            }
        });
    }
}

但是上面给出了以下错误:

[Doctrine\DBAL\Schema\SchemaException]                        
There is no column with name 'start_date' on table 'offers'. 

然而，注释掉“for 循环”意味着这个错误不再存在，这意味着问题就在那里。

也欢迎更好的方法!

Answer 1

回答了我自己的问题。我收到此错误的原因有两个。

原因 1，我要求一个列在另一个列之后，但它还不存在。

原因 2，我正在使用尚未创建的列创建报价。

应该这样做:

<?php

use App\Offer;
use App\Schedule;
use Carbon\Carbon;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class FixOffersTable extends Migration
{
    public function up()
    {
        DB::beginTransaction();

        Schema::table('offers', function(Blueprint $table)
        {
            $table->renameColumn('start_date', 'start_date_time');
            $table->renameColumn('end_date', 'end_date_time');
        });

        Schema::table('offers', function (Blueprint $table)
        {
            $table->time('start_time')->after('start_date_time')->nullable();
            $table->date('start_date')->after('start_date_time')->nullable();
        });


        foreach (Offer::all() as $offer) {
           /* Cannot use model mutator, as model class can change over time, and may no longer have certain columns
            in the $casts attribute. Therefore using the raw string fetched from the MySQL database. */
            $startDateTime = Carbon::createFromFormat('Y-m-d H:i:s', $offer->getOriginal('start_date_time'));
            $offer->start_date = Carbon::createFromDate($startDateTime->year, $startDateTime->month, $startDateTime->day);
            $offer->start_time = Carbon::createFromTime($startDateTime->hour, $startDateTime->minute, $startDateTime->second);
            $offer->save();
        }


        DB::commit();
    }
}