diff --git a/localtests/unsigned-modify/create.sql b/localtests/unsigned-modify/create.sql
new file mode 100644
index 0000000..9adbfd2
--- /dev/null
+++ b/localtests/unsigned-modify/create.sql
@@ -0,0 +1,26 @@
+drop table if exists gh_ost_test;
+create table gh_ost_test (
+  id bigint(20) NOT NULL AUTO_INCREMENT,
+  column1 int(11) NOT NULL,
+  column2 smallint(5) unsigned NOT NULL,
+  column3 mediumint(8) unsigned NOT NULL,
+  column4 tinyint(3) unsigned NOT NULL,
+  column6 int(11) NOT NULL,
+  PRIMARY KEY (id),
+  UNIQUE KEY c12_uix (column1, column2)
+) auto_increment=1;
+
+drop event if exists gh_ost_test;
+delimiter ;;
+create event gh_ost_test
+  on schedule every 1 second
+  starts current_timestamp
+  ends current_timestamp + interval 60 second
+  on completion not preserve
+  enable
+  do
+begin
+  -- mediumint maxvalue: 16777215 (unsigned), 8388607 (signed)
+  insert into gh_ost_test values (NULL, 13382498, 536,  8388607, 3, 1483892218);
+  insert into gh_ost_test values (NULL, 13382498, 536, 10000000, 3, 1483892218);
+end ;;
diff --git a/localtests/unsigned-modify/extra_args b/localtests/unsigned-modify/extra_args
new file mode 100644
index 0000000..bfa1c4d
--- /dev/null
+++ b/localtests/unsigned-modify/extra_args
@@ -0,0 +1 @@
+--alter="ADD UNIQUE INDEX (id), DROP INDEX c12_uix, DROP PRIMARY KEY,ADD PRIMARY KEY(column1,column2),MODIFY column2 SMALLINT UNSIGNED NOT NULL, MODIFY column3 INT NOT NULL"