diff --git a/installer/data/mysql/atomicupdate/bug_16402.sql b/installer/data/mysql/atomicupdate/bug_16402.sql
new file mode 100644
index 0000000000..914e791d44
--- /dev/null
+++ b/installer/data/mysql/atomicupdate/bug_16402.sql
@@ -0,0 +1,2 @@
+alter table letter modify column branchcode varchar(10) not null default '';
+alter table permissions modify column code varchar(64) not null default '';