my changes

database/migrations/2017_06_01_104359_create_books_table.php

@@ -0,0 +1,41 @@
+<?php
+
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class CreateBooksTable extends Migration {
+
+	/**
+	 * Run the migrations.
+	 *
+	 * @return void
+	 */
+	public function up()
+	{
+		Schema::create('books', function(Blueprint $table)
+		{
+			$table->increments('id');
+			$table->string('title');
+			$table->string('author');
+			$table->integer('year');
+			$table->integer('stock');
+			$table->integer('category_id')->unsigned();
+			$table->foreign('category_id')->references('id')->on('categories');
+			$table->integer('shelf_id')->unsigned();	
+			$table->foreign('shelf_id')->references('id')->on('shelves');		
+			$table->integer('year_id')->default('0');
+			$table->timestamps();
+		});
+	}
+
+	/**
+	 * Reverse the migrations.
+	 *
+	 * @return void
+	 */
+	public function down()
+	{
+		Schema::drop('books');
+	}
+
+}