Delete service variables when the option is deleted.

database/migrations/2017_10_03_233202_CascadeDeletionWhenServiceOptionIsDeleted.php

@@ -0,0 +1,32 @@
+<?php
+
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class CascadeDeletionWhenServiceOptionIsDeleted extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up()
+    {
+        Schema::table('service_variables', function (Blueprint $table) {
+            $table->dropForeign(['option_id']);
+
+            $table->foreign('option_id')->references('id')->on('service_options')->onDelete('CASCADE');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down()
+    {
+        Schema::table('service_variables', function (Blueprint $table) {
+            $table->dropForeign(['option_id']);
+
+            $table->foreign('option_id')->references('id')->on('service_options');
+        });
+    }
+}