title: Laravel/faker using invalid column names
body: <p>I'm running a Laravel 5.4 project created just three days ago. </p>
  
  <p>I have this in my <code>ModelFactory.php</code>:</p>
  
  <pre><code>$factory-&gt;define(\App\Models\Definition::class, function (Faker\Generator $faker) {
  $tag = "tag";
  $category = "cat";
  
  return [
      'name' =&gt; $faker-&gt;words,
      'description' =&gt; $faker-&gt;realText,
      'tags' =&gt; $tag,
      'price' =&gt; $faker-&gt;numberBetween(500, 50000),
      'category' =&gt; $category
  ];
  });
  </code></pre>
  
  <p>And in my <code>DatabaseSeeder.php</code>'s <code>run()</code>:</p>
  
  <pre><code>DB::table('definitions')-&gt;truncate();
  factory(Definition::class, 200)-&gt;create();
  </code></pre>
  
  <p>But when I run <code>db:seed</code>, i keep getting:</p>
  
  <blockquote>
    <p>SQLSTATE[HY000]: General error: 1 table definitions has no column named 0 (SQL: insert into "definitions" ("0", "1", "2") select quia as "0", No, there were no arches left, and all dripping wet, cross, and uncomfortable. The first thing
       I've got totag' (Alice had no reason to be ashamed of yourself for asking such a rule at processions;. as "1",
      1302 as "2" union all select cat as "0", 2017-03-17 10:51:53 as "1", 2017-03-17 10:51:53 as "2" uni
      on all select ? as "0", ? as "1", ? as "2" union all select ? as "0", ? as "1", ? as "2" union all select ? as "0",
       ? as "1", ? as "2" union all select ? as "0", ? as "1", ? as "2" union all select ? as "0", ? as "1", ? as "2")</p>
  </blockquote>
  
  <p>My table schema:</p>
  
  <pre><code>Schema::create('definitions', function (Blueprint $table) {
          $table-&gt;increments('id');
          $table-&gt;string('name');
          $table-&gt;string('description')-&gt;nullable();
          $table-&gt;integer('price');
          $table-&gt;json("tags");
          $table-&gt;string('category');
          $table-&gt;unsignedInteger('x_id')-&gt;nullable(); 
          $table-&gt;nullableTimestamps();
  </code></pre>
  
  <p>I have <code>$guarded = [];</code> in my Definition class. I'm thinking maybe this is some faker bug, because I'm out of ideas. </p>