add contract started_at field

console/migrations/m160302_171507_alter__table__contract__add__column__started_at.php

@@ -0,0 +1,31 @@
+<?php
+
+use yii\db\Schema;
+use yii\db\Migration;
+
+class m160302_171507_alter__table__contract__add__column__started_at extends Migration
+{
+    public function up()
+    {
+    	$this->addColumn("contract", "started_at", "datetime");
+    	$this->execute("update contract set started_at = created_at");
+    }
+
+    public function down()
+    {
+        echo "m160302_171507_alter__table__contract__add__column__started_at cannot be reverted.\n";
+
+        return false;
+    }
+
+    /*
+    // Use safeUp/safeDown to run migration code within a transaction
+    public function safeUp()
+    {
+    }
+
+    public function safeDown()
+    {
+    }
+    */
+}