UPDATE reports incorrect number of Rows affected

create table t2(a int, b int)engine=infinidb;

Query OK, 0 rows affected (0.20 sec)

MariaDB [test]> insert into t2 values (1, 2);

Query OK, 1 row affected (0.07 sec)

MariaDB [test]> insert into t2 values (3, 4);

Query OK, 1 row affected (0.04 sec)

MariaDB [test]> select * from t2;

+------+------+                                    

| a    | b    |

+------+------+

|    1 |    2 |

|    3 |    4 |

+------+------+

2 rows in set (0.03 sec)

MariaDB [test]> update t2 set a = 10;

{color:red}Query OK, 0 rows affected (0.06 sec)

Rows matched: 0  Changed: 0  Warnings: 0{color}

MariaDB [test]> select * from t2;

+------+------+                                    

| a    | b    |

+------+------+

|   10 |    2 |

|   10 |    4 |

+------+------+

2 rows in set (0.01 sec)