diff --git a/db_scripts/diff/15123.up b/db_scripts/diff/15123.up
index a935d932..d5ed5ca5 100644
--- a/db_scripts/diff/15123.up
+++ b/db_scripts/diff/15123.up
@@ -1,3 +1,4 @@
 use kamailio;
 
-alter table mobile_push_registrations add column device_id varbinary(255) not null after subscriber_id;
+alter table mobile_push_registrations add column device_id varbinary(255) not null after subscriber_id,
+  add key (device_id);