[#MDEV-30717] ROW_COUNT() after REPLACE of duplicit row returns 1

On table with single unique index:

CREATE TABLE `test` (

  `id` int(11) NOT NULL,

  `value` int(11) NOT NULL,

  UNIQUE KEY `id` (`id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_general_ci

ROW_COUNT() returns allways 1, even for duplicate rows:

REPLACE INTO test VALUES (1,1); SELECT ROW_COUNT(); REPLACE INTO test VALUES (1,1); SELECT ROW_COUNT();

Query OK, 1 row affected (0.000 sec)

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

| ROW_COUNT() |

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

|           1 |

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

1 row in set (0.000 sec)

Query OK, 1 row affected (0.000 sec)

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

| ROW_COUNT() |

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

|           1 |

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

1 row in set (0.000 sec)

On table with multiple indexes:

CREATE TABLE `test` (

  `id` int(11) NOT NULL,

  `value` int(11) NOT NULL,

  UNIQUE KEY `id` (`id`),

  UNIQUE KEY `value` (`value`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_general_ci

ROW_COUNT() returns correct result according to documentation (1 and then 2):

REPLACE INTO test VALUES (1,1); SELECT ROW_COUNT(); REPLACE INTO test VALUES (1,1); SELECT ROW_COUNT();

Query OK, 1 row affected (0.000 sec)

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

| ROW_COUNT() |

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

|           1 |

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

1 row in set (0.000 sec)

Query OK, 2 rows affected (0.000 sec)

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

| ROW_COUNT() |

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

|           2 |

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

1 row in set (0.000 sec)

[MDEV-30717] ROW_COUNT() after REPLACE of duplicit row returns 1 Created: 2023-02-23 Updated: 2023-11-28
Status:	Confirmed
Project:	MariaDB Server
Component/s:	Server
Affects Version/s:	10.6.11
Fix Version/s:	10.6, 10.11