mysql - MySQL-帮助我更改此搜索查询以获得所需结果

以下是回答理解系统所需的表和数据的转储：-

该系统由导师和课程组成。
表All_Tag_Relations中的数据存储注册的每个导师和导师创建的每个类的标签关系。标签关系用于搜索类别。

CREATE TABLE IF NOT EXISTS `Tags` (
  `id_tag` int(10) unsigned NOT NULL auto_increment,
  `tag` varchar(255) default NULL,
  PRIMARY KEY  (`id_tag`),
  UNIQUE KEY `tag` (`tag`),
  KEY `id_tag` (`id_tag`),
  KEY `tag_2` (`tag`),
  KEY `tag_3` (`tag`),
  KEY `tag_4` (`tag`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1;

INSERT INTO `Tags` (`id_tag`, `tag`) VALUES
(1, 'Sandeepan'),
(2, 'Nath'),
(3, 'first'),
(4, 'class'),
(5, 'new'),
(6, 'Bob'),
(7, 'Cratchit');


CREATE TABLE IF NOT EXISTS `All_Tag_Relations` (
  `id_tag` int(10) unsigned NOT NULL default '0',
  `id_tutor` int(10) default NULL,
  `id_wc` int(10) unsigned default NULL,
  KEY `All_Tag_Relations_FKIndex1` (`id_tag`),
  KEY `id_wc` (`id_wc`),
  KEY `id_tag` (`id_tag`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;


INSERT INTO `All_Tag_Relations` (`id_tag`, `id_tutor`, `id_wc`) VALUES
(1, 1, NULL),
(2, 1, NULL),
(3, 1, 1),
(4, 1, 1),
(6, 2, NULL),
(7, 2, NULL),
(5, 2, 2),
(4, 2, 2),
(8, 1, 3),
(9, 1, 3);

以下是我的查询：

此查询搜索“第一类”（“标记”表中“ first = 3”和“ class = 4”的标记）并返回所有这些类，以使术语“ first”和“ class”都出现在类名称中。

SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS
       key_1_total_matches,
       SUM(DISTINCT( wtagrels.id_tag =4))                AS
       key_2_total_matches
FROM   all_tag_relations AS wtagrels
WHERE  ( wtagrels.id_tag =3
          OR wtagrels.id_tag =4 )
GROUP  BY wtagrels.id_wc
HAVING key_1_total_matches = 1
       AND key_2_total_matches = 1
LIMIT  0, 20

并返回id_wc = 1的类。

但是，我希望搜索显示所有这些类，以便所有搜索项都出现在类名称或其导师名称中
因此，搜索“ Sandeepan类”（wtagrels.id_tag = 1,4）或“ Sandeepan Nath”也将返回id_wc = 1的类。和搜索。搜索“鲍勃优先”不应返回任何类。

如果可能的话，请使用MyIsam-全文搜索修改上面的查询或建议一个新查询，但是以某种方式可以帮助我获得结果。

最佳答案

我认为此查询将帮助您：

SET @tag1 = 1, @tag2 = 4; -- Setting some user variables to see where the ids go. (you can put the values in the query)

SELECT wtagrels.id_wc,
  SUM(DISTINCT( wtagrels.id_tag =@tag1 OR wtagrels.id_tutor =@tag1)) AS key_1_total_matches,
  SUM(DISTINCT( wtagrels.id_tag =@tag2 OR wtagrels.id_tutor =@tag2)) AS key_2_total_matches
FROM   all_tag_relations AS wtagrels
WHERE  ( wtagrels.id_tag =@tag1 OR wtagrels.id_tag =@tag2 )
GROUP  BY wtagrels.id_wc
HAVING key_1_total_matches = 1 AND key_2_total_matches = 1
LIMIT  0, 20

返回id_wc = 1。
对于（6，3），查询不返回任何内容。