diff --git a/db-test/index.php b/db-test/index.php
index 3b51870..f41148b 100644
--- a/db-test/index.php
+++ b/db-test/index.php
@@ -3,6 +3,8 @@ require_once 'vendor/autoload.php';
 
 $dotenv = Dotenv\Dotenv::createImmutable(__DIR__);
 $dotenv->safeLoad();
+
+// Use environment variables for the database password and IP address.
 $db_pass = $_ENV['DATABASE_PASSWORD'];
 $ip_addr = $_ENV['IP_ADDRESS'];