diff --git a/database/DDL.sql b/database/DDL.sql
index 3fe3e79..b4bf5b0 100644
--- a/database/DDL.sql
+++ b/database/DDL.sql
@@ -25,7 +25,7 @@ CREATE TABLE `book` (
 CREATE TABLE `dvd` (
   `id` int unsigned NOT NULL AUTO_INCREMENT,
   `product_id` int unsigned NOT NULL,
-  `size` int unsigned NOT NULL,
+  `size` float NOT NULL,
   PRIMARY KEY (`id`),
   UNIQUE KEY `dvd_UN` (`product_id`),
   CONSTRAINT `dvd_FK` FOREIGN KEY (`product_id`) REFERENCES `product` (`id`)
diff --git a/src/Model/DVD.php b/src/Model/DVD.php
index a8cb60c..7f7b91b 100644
--- a/src/Model/DVD.php
+++ b/src/Model/DVD.php
@@ -74,7 +74,7 @@ class DVD extends Product
         $size = $this->getSize();
 
         $stmt = $conn->prepare("INSERT INTO ".DVD." (product_id, size) VALUES (?, ?);");
-        $stmt->bind_param('ii', $productId, $size);
+        $stmt->bind_param('id', $productId, $size);
 
         if ($stmt->execute() === true) {
             $this->setVariationId($conn->insert_id);