Question

我有3张桌子：

CREATE TABLE IF NOT EXISTS `Articles` (
  `id` int(11) NOT NULL DEFAULT '',
  ...
  ...
  PRIMARY KEY (`id_article`)
) ENGINE=InnoDB ;

Persons_Articles：

CREATE TABLE IF NOT EXISTS `Persons_Articles` (
  `id_article` int(11) NOT NULL,
  `id_person` int(11) UNSIGNED NOT NULL,
  `role` TINYINT(4) UNSIGNED,
  PRIMARY KEY (`id_article`,`id_person`,`role`)
) ENGINE=InnoDB ;

人：

CREATE TABLE IF NOT EXISTS `Persons` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `firstname` varchar(64) DEFAULT NULL,
  `lastname` varchar(64) NOT NULL,
  `fullname` varchar(128) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB ;

INSERT INTO Articles VALUES (1, 'A'), (2, 'B'), (3, 'B');
INSERT INTO Persons_Articles VALUES (1, 1, 1);
INSERT INTO Persons_Articles VALUES (1, 2, 2);
INSERT INTO Persons VALUES (1, 'Mick', 'Jagger', 'Mick Jagger');
INSERT INTO Persons VALUES (2, 'Keith', 'Richards', 'Keith Richards');

我查找一个可以返回文章的查询（fullname ='Mick Jagger'AND role = 1）AND（fullname ='Keith Richards'AND role = 2）

有什么想法吗？

Answer 1

尝试执行以下操作：

SELECT * FROM Persons P
INNER JOIN Persons_Articles PA ON PA.id_person = P.id
INNER JOIN Articles A ON A.id = PA.id_article
WHERE (P.fullname = 'Mick Jagger' AND PA.role = 1) OR (P.fullname = 'Keith Richards' AND PA.role = 2)

Answer 2

这假定您不能拥有文章的副本（名称和角色）：

  SELECT a.*
    FROM articles a
    JOIN persons_articles pa
      ON pa.id_article = a.id
    JOIN persons p
      ON pa.id_person = p.id
     AND ((p.fullname = 'Mick Jagger' AND pa.role = 1) OR (p.fullname = 'Keith Richards' AND pa.role = 2))
GROUP BY a.id
  HAVING count(*) = 2;

<强>更新

作为旁注，我永远不会将全名存储在数据库中..这会导致UPDATE和INSERT的更多工作，如果你不小心，你可以最终得到不匹配的名字。虽然工作稍微多一点，但如果需要，您可以随时CONCAT()。

MySQL类型的联合

2 个答案: