1 files changed, 16 insertions, 0 deletions
diff --git a/mysql-test/t/alter_table.test b/mysql-test/t/alter_table.test
index d7f7a12cbf8..5b5fdf50c16 100644
--- a/mysql-test/t/alter_table.test
+++ b/mysql-test/t/alter_table.test
@@ -1128,3 +1128,19 @@ INSERT INTO t1 VALUES (1), (2);
 ALTER TABLE t1 ADD COLUMN (f1 INT), ADD COLUMN (f2 INT), ADD KEY f2k(f2);
 DROP TABLE t1;
 
+
+--echo #
+--echo # Test for bug #53820 "ALTER a MEDIUMINT column table causes full
+--echo #                      table copy".
+--echo #
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+CREATE TABLE t1 (a INT, b MEDIUMINT);
+INSERT INTO t1 VALUES (1, 1), (2, 2);
+--echo # The below ALTER should not copy table and so no rows should
+--echo # be shown as affected.
+--enable_info
+ALTER TABLE t1 CHANGE a id INT;
+--disable_info
+DROP TABLE t1;