[#MDEV-8780] fulltext index on innodb table doesn't honor ft_min_word

innodb tables, doesn't use the ft_min_word_len, unlike myisam table, the ft_min_word_len, used by innodb table is always 4 (as the default value).

ex:

CREATE TABLE `ftx` (

  `id` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT,

  `_search` VARCHAR(250) DEFAULT NULL,

  PRIMARY KEY (`id`),

  FULLTEXT KEY `search` (`_search`)

) ENGINE=INNODB DEFAULT CHARSET=utf8;

INSERT INTO ftx (_search) VALUES ('yi wu') ;

INSERT INTO ftx (_search) VALUES ('yi wux') ;

INSERT INTO ftx (_search) VALUES ('yi wuxo') ;

mysql> SELECT * FROM ftx;

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

| id | _search |

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

|  1 | yi wu   |

|  2 | yi wux  |

|  3 | yi wuxo |

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

mysql> SHOW VARIABLES LIKE 'ft_min_word_len';

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

| Variable_name   | Value |

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

| ft_min_word_len | 2     |

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

mysql> SELECT * FROM `ftx` WHERE (MATCH (_search) AGAINST ('wu')) ;

Empty set (0.00 sec)

and with isam table that's ok.

DROP TABLE ftx;

CREATE TABLE `ftx` (

  `id` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT,

  `_search` VARCHAR(250) DEFAULT NULL,

  PRIMARY KEY (`id`),

  FULLTEXT KEY `search` (`_search`)

) ENGINE=MYISAM DEFAULT CHARSET=utf8;

INSERT INTO ftx (_search) VALUES ('yi wu') ;

INSERT INTO ftx (_search) VALUES ('yi wux') ;

INSERT INTO ftx (_search) VALUES ('yi wuxo') ;

mysql> SELECT * FROM `ftx` WHERE (MATCH (_search) AGAINST ('wu')) ;

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

| id | _search |

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

|  1 | yi wu   |

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

1 row in set (0.00 sec)

[MDEV-8780] fulltext index on innodb table doesn't honor ft_min_word_len Created: 2015-09-09 Updated: 2015-11-03 Resolved: 2015-09-10
Status:	Closed
Project:	MariaDB Server
Component/s:	Documentation, Full-text Search
Affects Version/s:	10.0.21
Fix Version/s:	N/A