MySQL insert on duplicate update for non-PRIMARY key

Question

I am little confused with insert on duplicate update query. I have MySQL table with structure like this:

• record_id (PRIMARY, UNIQUE)
• person_id (UNIQU

Answer 1

13.2.5.3 INSERT ... ON DUPLICATE KEY UPDATE Syntax

If you specify ON DUPLICATE KEY UPDATE, and a row is inserted that would cause a duplicate value in a UNIQUE index or PRIMARY KEY, MySQL performs an UPDATE of the old row.

Example:

DELIMITER //

DROP PROCEDURE IF EXISTS `sp_upsert`//
DROP TABLE IF EXISTS `table_test`//

CREATE TABLE `table_test` (
  `record_id` INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
  `person_id` INT UNSIGNED NOT NULL,
  `some_text` VARCHAR(50),
  `some_other_text` VARCHAR(50),
  UNIQUE KEY `record_id_index` (`record_id`),
  UNIQUE KEY `person_id_index` (`person_id`)
)//

INSERT INTO `table_test`
  (`person_id`, `some_text`, `some_other_text`)
VALUES
  (1, 'AAA', 'XXX'),
  (2, 'BBB', 'YYY'),
  (3, 'CCC', 'ZZZ')//

CREATE PROCEDURE `sp_upsert`(
  `p_person_id` INT UNSIGNED,
  `p_some_text` VARCHAR(50),
  `p_some_other_text` VARCHAR(50)
)
BEGIN
  INSERT INTO `table_test`
    (`person_id`, `some_text`, `some_other_text`)
  VALUES
    (`p_person_id`, `p_some_text`, `p_some_other_text`)
  ON DUPLICATE KEY UPDATE `some_text` = `p_some_text`,
                          `some_other_text` = `p_some_other_text`;
END//

DELIMITER ;

mysql> CALL `sp_upsert`(1, 'update_text_0', 'update_text_1');
Query OK, 2 rows affected (0.00 sec)

mysql> SELECT
    ->   `record_id`,
    ->   `person_id`,
    ->   `some_text`,
    ->   `some_other_text`
    -> FROM
    ->   `table_test`;
+-----------+-----------+---------------+-----------------+
| record_id | person_id | some_text     | some_other_text |
+-----------+-----------+---------------+-----------------+
|         1 |         1 | update_text_0 | update_text_1   |
|         2 |         2 | BBB           | YYY             |
|         3 |         3 | CCC           | ZZZ             |
+-----------+-----------+---------------+-----------------+
3 rows in set (0.00 sec)

mysql> CALL `sp_upsert`(4, 'new_text_0', 'new_text_1');
Query OK, 1 row affected (0.00 sec)

mysql> SELECT
    ->   `record_id`,
    ->   `person_id`,
    ->   `some_text`,
    ->   `some_other_text`
    -> FROM
    ->   `table_test`;
+-----------+-----------+---------------+-----------------+
| record_id | person_id | some_text     | some_other_text |
+-----------+-----------+---------------+-----------------+
|         1 |         1 | update_text_0 | update_text_1   |
|         2 |         2 | BBB           | YYY             |
|         3 |         3 | CCC           | ZZZ             |
|         5 |         4 | new_text_0    | new_text_1      |
+-----------+-----------+---------------+-----------------+
4 rows in set (0.00 sec)

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