MySQL Requête avec des valeurs vides possibles sur la jointure

Question

Je ne suis pas très "brillant" quand il s'agit de requêtes MySQL plus sérieuses que d'habitude. Donc, un peu d'aide est nécessaire.

J'ai tables comme suit:

CREATE TABLE IF NOT EXISTS `clients` (
    `c_id` int(11) NOT NULL AUTO_INCREMENT, 
    `c_name` varchar(255) COLLATE utf8_unicode_ci NOT NULL, 
    PRIMARY KEY (`c_id`) 
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ; 

INSERT INTO `clients` (`c_name`) VALUES ('client1'); 
INSERT INTO `clients` (`c_name`) VALUES ('client2'); 
INSERT INTO `clients` (`c_name`) VALUES ('client3'); 
INSERT INTO `clients` (`c_name`) VALUES ('client4'); 
INSERT INTO `clients` (`c_name`) VALUES ('client5'); 

CREATE TABLE IF NOT EXISTS `people` (
    `p_id` int(11) NOT NULL AUTO_INCREMENT, 
    `p_mark` int(1) NOT NULL DEFAULT '0', 
    `p_client_id` int(11) DEFAULT NULL, 
    `p_name` varchar(45) COLLATE utf8_unicode_ci NOT NULL, 
    `p_source` varchar(45) COLLATE utf8_unicode_ci NOT NULL DEFAULT '--', 
    `p_segment` varchar(45) COLLATE utf8_unicode_ci NOT NULL DEFAULT '--', 
    `p_date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, 
    PRIMARY KEY (`p_id`) 
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ; 

INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('0','1','John','AA','3',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('0','2','Alex','BB','23',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('1','4','Ivan','-','-',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('0','4','Stan','FF','5',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('1','1','Paul','DD','12',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('1','4','Greg','-','-',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('0','1','Eric','EE','7',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('1','5','Thom','BB','92',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('0','4','Finn','BB','41',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('0','2','Leon','CC','21',NOW()); 
INSERT INTO `people` (`p_mark`,`p_client_id`,`p_name`,`p_source`,`p_segment`,`p_date`) VALUES ('1','2','Sean','AA','25',NOW()); 

CREATE TABLE IF NOT EXISTS `sources` (
    `src_id` int(11) NOT NULL AUTO_INCREMENT, 
    `src_name` varchar(45) COLLATE utf8_unicode_ci NOT NULL, 
    `src_abbr` varchar(10) COLLATE utf8_unicode_ci NOT NULL, 
    `src_client` int(11) NOT NULL, 
    PRIMARY KEY (`src_id`) 
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ; 

INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Aoo oo','AA',1); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Boo oo','BB',2); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Boo oo','BB',4); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Coo oo','CC',1); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Doo oo','DD',1); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Eoo oo','EE',4); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Foo oo','FF',5); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Aoo oo','AA',2); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Boo oo','BB',5); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Coo oo','CC',2); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Doo oo','DD',4); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Eoo oo','EE',1); 
INSERT INTO `sources` (`src_name`,`src_abbr`,`src_client`) VALUES ('Foo oo','FF',4); 

CREATE TABLE IF NOT EXISTS `segments` (
    `seg_id` int(11) NOT NULL AUTO_INCREMENT, 
    `seg_client_id` int(11) NOT NULL, 
    `seg_src_id` int(11) NOT NULL, 
    `seg_number` int(11) NOT NULL, 
    `seg_value` varchar(255) COLLATE utf8_unicode_ci NOT NULL, 
    PRIMARY KEY (`seg_id`) 
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ; 

INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','1','3','aa-Seg-c1'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('0','2','23','bb-Seg-c2'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','4','5','ff-Seg-c4'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','1','12','dd-Seg-c1'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','1','7','ee-Seg-c1'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','5','92','bb-Seg-c5'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','4','41','bb-Seg-c4'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','2','21','cc-Seg-c2'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','2','25','aa-Seg-c2'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','3','35','tt-Seg-c3'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','3','11','rr-Seg-c3'); 
INSERT INTO `segments` (`seg_client_id`,`seg_src_id`,`seg_number`,`seg_value`) VALUES ('1','5','7','zz-Seg-c5'); 

Je suis en train de sélectionner toutes les lignes de people limitées par p_client_id 4 avec la requête suivante:

SELECT 
    `people`.* 
    `clients`.*, 
    `sources`.*, 
    `segments`.* 
FROM 
    `people` 
INNER JOIN 
    `clients` ON `people`.`p_client_id` = `clients`.`c_id` 
LEFT JOIN 
    `sources` ON `people`.`p_source` = `sources`.`src_abbr` 
RIGHT JOIN 
    `segments` ON `people`.`p_segment` = `segments`.`seg_number` 
WHERE 
    `p_client_id` = '4' 
GROUP BY 
    `people`.`p_id` 
ORDER BY `people`.`p_date` DESC; 

La chose est, que la mention requête suppose de retourner 4 lignes, mais la jointure ne parvient pas à retourner les lignes où people. p_source et people. p_segment sont manquants.

Tout conseil est fortement apprécié!

a également préparé sqlfiddle:http://sqlfiddle.com/#!2/0c54c/1

Answer 1

Modifier la jonction avec segments d'un droit à une REJOIGNEZ LEFT JOIN. Une jointure à droite inclut uniquement les lignes correspondantes de la table de droite de la jointure (segments).