Improve scheduled task layout and data handling

database/migrations/2016_03_18_155649_add_nullable_field_lastrun.php

@@ -0,0 +1,29 @@
+<?php
+
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class AddNullableFieldLastrun extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        $table = DB::getQueryGrammar()->wrapTable('tasks');
+        DB::statement('ALTER TABLE '.$table.' CHANGE `last_run` `last_run` TIMESTAMP NULL;');
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        $table = DB::getQueryGrammar()->wrapTable('tasks');
+        DB::statement('ALTER TABLE '.$table.' CHANGE `last_run` `last_run` TIMESTAMP;');
+    }
+}