dongqiang2358 2017-05-08 14:01
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使用ID数组播种Laravel不起作用

I try to do seeding on a pivot table. Here is my code

public function run()
{
    // Get array of ids
    $teacherIds = DB::table('teachers')->pluck('id');
    $courseIds  = DB::table('courses')->pluck('id');

    // Seed course_teacher table
    foreach ((range(1, 1)) as $index)
    {
        DB::table('course_teacher')->insert(
            [
                'teacher_id' => $teacherIds[array_rand( (array) $teacherIds)],
                'course_id' => $courseIds[array_rand( (array) $courseIds)]
            ]
        );
    }
}

I added (array) because I had an error that I was giving an object while it wanted an array.

But since I have another error undefined index:

Can you help me ? Thank you very much

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1条回答 默认 最新

  • download2014711 2017-05-08 14:08
    关注

    To make sure you get an array when getting $teacherIds and $courseIds, add the toArray function to make sure you are getting an array and not a Collection object.

    // Get array of ids
    $teacherIds = DB::table('teachers')->pluck('id')->toArray();
    $courseIds  = DB::table('courses')->pluck('id')->toArray();
    

    By doing this, you don't need to cast the array in the array_rand function either.

    Update:

    Even better would be to use the random function. This function will choose a random element for you.

    $teacherIds = DB::table('teachers')->pluck('id');
    $courseIds  = DB::table('courses')->pluck('id');
    
    DB::table('course_teacher')->insert(
        [
            'teacher_id' => $teacherIds->random(),
            'course_id' => $courseIds->random()
        ]
    );
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

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