As per the JDBC 4.1 spec (15.2.3 Retrieving Values -
Synopsis:

http://download.oracle.com/otn-pub/jcp/jdbc-4_1-mrel-spec/jdbc4.1-fr-spec.pdf
), If a select list contains the same column more than once, the first instance of the column should be returned. The mariadb java client returns the last instance.

How To Repeat:

– Create two tables with the same column name and a relationship between the tables using table1.id=table2.fk
CREATE TABLE `table1` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`attempt` int(11) NOT NULL DEFAULT '0',
`description` varchar(50) NOT NULL DEFAULT 'description-table1',
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=4 ;

CREATE TABLE `table2` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`fk` int(11) NOT NULL,
`attempt` int(11) NOT NULL DEFAULT '0',
`description2` varchar(50) NOT NULL DEFAULT 'description-table2',
PRIMARY KEY (`id`),
KEY `fk` (`fk`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=4 ;

ALTER TABLE `table2`
ADD CONSTRAINT `table2_ibfk_1` FOREIGN KEY (`fk`) REFERENCES `table1` (`id`);

– Insert three records into table1, two matching records into table2, so there is one set of nulls
INSERT INTO `table1` (`id`, `attempt`, `description`) VALUES
(1, 1, 'matched1'),
(2, 2, 'unmatched2'),
(3, 3, 'matched3');

INSERT INTO `table2` (`id`, `fk`, `attempt`, `description2`) VALUES
(1, 1, 1, 'description1-table2'),
(3, 3, 3, 'description3-table2');

– Select data with outer join including nulls using wildcard and named columns
SELECT t1.id, t1.attempt, t1.description, t2.* FROM table1 t1 LEFT OUTER JOIN table2 t2 ON t2.fk=t1.id;

Results having duplicate columns through left outer join:

mysql> SELECT t1.id, t1.attempt, t1.description, t2.* FROM table1 t1 LEFT OUTER JOIN table2 t2 ON t2.fk=t1.id;
--------------------------------------------------------

--------------------------------------------------------

--------------------------------------------------------
3 rows in set (0.00 sec)

– Finding the column "attempt"
rs.findColumn("attempt") gives us "6" . Should be "2"

PS: The findColumn strategy is used heavily by ORM frameworks like Hibernate for Mapping objects and causes severe failures as a result of this bug.