math_cms/app/Models/StudentExercise.php

<?php

namespace App\Models;

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

class StudentExercise extends Model
{
    use HasFactory;

    protected $fillable = [
        'student_id',
        'question_id',
        'knowledge_point_id',
        'question_content',
        'student_answer',
        'correct_answer',
        'is_correct',
        'submission_status',
        'batch_id',
        'kp_code',
        'selected_skills',
        'skill_scores',
        'time_spent_seconds',
        'difficulty_level',
        'created_at',
        'updated_at',
    ];

    protected $casts = [
        'is_correct' => 'boolean',
        'knowledge_point_id' => 'integer',
        'selected_skills' => 'array',
        'skill_scores' => 'array',
        'time_spent_seconds' => 'integer',
        'difficulty_level' => 'float',
        'created_at' => 'datetime',
        'updated_at' => 'datetime',
    ];
}