diff --git a/localtests/alter-charset-all-dml/create.sql b/localtests/alter-charset-all-dml/create.sql
new file mode 100644
index 0000000..3126a04
--- /dev/null
+++ b/localtests/alter-charset-all-dml/create.sql
@@ -0,0 +1,28 @@
+drop table if exists gh_ost_test;
+create table gh_ost_test (
+  id int auto_increment,
+  t1 varchar(128)  charset latin1 collate latin1_swedish_ci,
+  t2 varchar(128)  charset latin1 collate latin1_swedish_ci,
+  tutf8 varchar(128) charset utf8,
+  tutf8mb4 varchar(128) charset utf8mb4,
+  random_value varchar(128) charset ascii,
+  primary key(id)
+) 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
+  insert into gh_ost_test values (null, md5(rand()), md5(rand()), md5(rand()), md5(rand()), md5(rand()));
+  insert into gh_ost_test values (null, 'átesting', 'átesting', 'átesting', 'átesting', md5(rand()));
+  insert into gh_ost_test values (null, 'átesting_del', 'átesting', 'átesting', 'átesting', md5(rand()));
+  insert into gh_ost_test values (null, 'testátest', 'testátest', 'testátest', '🍻😀', md5(rand()));
+  update gh_ost_test set t1='átesting2' where t1='átesting' order by id desc limit 1;
+  delete from gh_ost_test where t1='átesting_del' order by id desc limit 1;
+end ;;
diff --git a/localtests/alter-charset-all-dml/extra_args b/localtests/alter-charset-all-dml/extra_args
new file mode 100644
index 0000000..c39b022
--- /dev/null
+++ b/localtests/alter-charset-all-dml/extra_args
@@ -0,0 +1 @@
+--alter='MODIFY `t1` varchar(128) CHARACTER SET utf8mb4 NOT NULL, MODIFY `t2` varchar(128) CHARACTER SET latin2 NOT NULL, MODIFY `tutf8` varchar(128) CHARACTER SET latin1 NOT NULL'