diff --git a/installer/data/mysql/atomicupdate/bug_30451_do_not_delete_orders_with_subscription.pl b/installer/data/mysql/atomicupdate/bug_30451_do_not_delete_orders_with_subscription.pl
new file mode 100755
index 0000000000..bb3b7747fc
--- /dev/null
+++ b/installer/data/mysql/atomicupdate/bug_30451_do_not_delete_orders_with_subscription.pl
@@ -0,0 +1,22 @@
+use Modern::Perl;
+
+return {
+    bug_number  => "30451",
+    description => "Update FK constraint on aqorders.subscriptionid to ON DELETE SET NULL",
+    up          => sub {
+        my ($args) = @_;
+        my ( $dbh, $out ) = @$args{qw(dbh out)};
+
+        if ( foreign_key_exists( 'aqorders', 'aqorders_subscriptionid' ) ) {
+            $dbh->do(q{
+                ALTER TABLE aqorders
+                DROP FOREIGN KEY aqorders_subscriptionid
+            });
+        }
+        $dbh->do(q{
+            ALTER TABLE aqorders
+            ADD CONSTRAINT `aqorders_subscriptionid` FOREIGN KEY (`subscriptionid`) REFERENCES subscription(`subscriptionid`) ON DELETE SET NULL ON UPDATE CASCADE
+        });
+        say $out "Update FK constraint on subscriptionid";
+    },
+};
diff --git a/installer/data/mysql/kohastructure.sql b/installer/data/mysql/kohastructure.sql
index ba5305fd30..34aca0332b 100644
--- a/installer/data/mysql/kohastructure.sql
+++ b/installer/data/mysql/kohastructure.sql
@@ -707,7 +707,7 @@ CREATE TABLE `aqorders` (
   CONSTRAINT `aqorders_ibfk_1` FOREIGN KEY (`basketno`) REFERENCES `aqbasket` (`basketno`) ON DELETE CASCADE ON UPDATE CASCADE,
   CONSTRAINT `aqorders_ibfk_2` FOREIGN KEY (`biblionumber`) REFERENCES `biblio` (`biblionumber`) ON DELETE SET NULL ON UPDATE CASCADE,
   CONSTRAINT `aqorders_ibfk_3` FOREIGN KEY (`invoiceid`) REFERENCES `aqinvoices` (`invoiceid`) ON DELETE SET NULL ON UPDATE CASCADE,
-  CONSTRAINT `aqorders_subscriptionid` FOREIGN KEY (`subscriptionid`) REFERENCES `subscription` (`subscriptionid`) ON DELETE CASCADE ON UPDATE CASCADE
+  CONSTRAINT `aqorders_subscriptionid` FOREIGN KEY (`subscriptionid`) REFERENCES `subscription` (`subscriptionid`) ON DELETE SET NULL ON UPDATE CASCADE
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 /*!40101 SET character_set_client = @saved_cs_client */;