我试图全文搜索与标签，但它并没有正常工作对我来说赤附加的图像，请
MYsql FULLTEXT查询产生意想不到的排名;为什么？
查询是：
SELECT *,
MATCH(tags) AGAINST ('tag3 tag6 tag4') AS score
FROM items
ORDER BY score DESC
为何成绩不按照正确的顺序排序字段？如果你检查第二行有我搜索的所有标签，而第一个字段没有tag3关键字。
我的意思是标识字段顺序应该是：5,1,2 ...等和NOT 1,5,2..etc
哪里是我的错？
然后我想首先在标签字段中搜索，然后如果没有结果我想搜索与FULLTEXT内部描述字段相同的关键字，那么用户将在标签和描述中搜索标签和描述，如果标签不匹配，是否有可能在相同的查询或我需要两个分离的查询？
在本文档中http://dev.mysql.com/doc/refman/5.0/en/fulltext-natural-language.html它说：“对于非常小的表格，单词分布没有充分反映它们的语义值，并且此模型有时可能会产生奇怪的结果。”
如果您的物品表很小 - 例如样品表 - 您可能会遇到这个问题并得到一个“奇怪”的结果。
您不妨试试这个查询IN BOOLEAN MODE，看看您的结果是否符合您的预测。尝试这个。
SELECT *,
MATCH(tags) AGAINST ('tag3 tag6 tag4' IN BOOLEAN MODE) AS score
FROM items
ORDER BY score DESC
布尔模式会禁用单词分配排名。注意，你应该理解自然语言和布尔模式之间的区别，一旦你有一个体面大小的表，明智地选择使用哪一个。如果您正在寻找博客所拥有的标签类型，布尔可能是一条可行的路。
首先，这里是您的示例数据加载到MySQL 5.5。12我的Windows7机器
mysql> DROP DATABASE IF EXISTS lspuk;
Query OK, 1 row affected (0.00 sec)
mysql> CREATE DATABASE lspuk;
Query OK, 1 row affected (0.00 sec)
mysql> USE lspuk
Database changed
mysql> CREATE TABLE items
-> (
-> id int not null auto_increment,
-> description VARCHAR(30),
-> tags VARCHAR(30),
-> primary key (id),
-> FULLTEXT tags_ftndx (tags)
->) ENGINE=MyISAM;
Query OK, 0 rows affected (0.04 sec)
mysql> INSERT INTO items (description,tags) VALUES
-> ('the first' ,'tag1 tag3 tag4'),
-> ('the second','tag5 tag1 tag2'),
-> ('the third' ,'tag5 tag1 tag9'),
-> ('the fourth','tag5 tag6 tag2'),
-> ('the fifth' ,'tag4 tag3 tag6'),
-> ('the sixth' ,'tag2 tag3 tag6');
Query OK, 6 rows affected (0.00 sec)
Records: 6 Duplicates: 0 Warnings: 0
mysql>
请看看标签人口在MySQL中发生的方式：
mysql> SELECT 'tag1',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag1%' UNION
-> SELECT 'tag2',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag2%' UNION
-> SELECT 'tag3',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag3%' UNION
-> SELECT 'tag4',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag4%' UNION
-> SELECT 'tag5',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag5%' UNION
-> SELECT 'tag6',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag6%' UNION
-> SELECT 'tag9',COUNT(1) tag_count FROM items WHERE tags LIKE '%tag9%';
+------+-----------+
| tag1 | tag_count |
+------+-----------+
| tag1 | 3 |
| tag2 | 3 |
| tag3 | 3 |
| tag4 | 2 |
| tag5 | 3 |
| tag6 | 3 |
| tag9 | 1 |
+------+-----------+
7 rows in set (0.00 sec)
mysql>
细心观察，请注意以下事实：
如果删除TAG4和运行查询，你会得到所有
mysql> SELECT *,MATCH(tags) AGAINST ('tag3 tag6') as score FROM items ORDER BY score DESC;
+----+-------------+----------------+-------+
| id | description | tags | score |
+----+-------------+----------------+-------+
| 1 | the first | tag1 tag3 tag4 | 0 |
| 2 | the second | tag5 tag1 tag2 | 0 |
| 3 | the third | tag5 tag1 tag9 | 0 |
| 4 | the fourth | tag5 tag6 tag2 | 0 |
| 5 | the fifth | tag4 tag3 tag6 | 0 |
| 6 | the sixth | tag2 tag3 tag6 | 0 |
+----+-------------+----------------+-------+
6 rows in set (0.00 sec)
的评价方法，似乎没有得分是基于平均数令牌场和存在和/或不存在特定值的以特定的顺序影响评分。如果您可以将不同风格的得分和标签规范的，要注意各种得分：
mysql> SELECT *,MATCH(tags) AGAINST ('tag3 tag6 tag4') as score FROM items ORDER BY score DESC;
+----+-------------+----------------+--------------------+
| id | description | tags | score |
+----+-------------+----------------+--------------------+
| 1 | the first | tag1 tag3 tag4 | 0.6700310707092285 |
| 5 | the fifth | tag4 tag3 tag6 | 0.6700310707092285 |
| 2 | the second | tag5 tag1 tag2 | 0 |
| 3 | the third | tag5 tag1 tag9 | 0 |
| 4 | the fourth | tag5 tag6 tag2 | 0 |
| 6 | the sixth | tag2 tag3 tag6 | 0 |
+----+-------------+----------------+--------------------+
6 rows in set (0.00 sec)
mysql> SELECT *,MATCH(tags) AGAINST ('tag3 tag6 tag4' IN BOOLEAN MODE) as score FROM items ORDER BY score DESC;
+----+-------------+----------------+-------+
| id | description | tags | score |
+----+-------------+----------------+-------+
| 5 | the fifth | tag4 tag3 tag6 | 3 |
| 1 | the first | tag1 tag3 tag4 | 2 |
| 6 | the sixth | tag2 tag3 tag6 | 2 |
| 4 | the fourth | tag5 tag6 tag2 | 1 |
| 2 | the second | tag5 tag1 tag2 | 0 |
| 3 | the third | tag5 tag1 tag9 | 0 |
+----+-------------+----------------+-------+
6 rows in set (0.00 sec)
mysql> SELECT *,MATCH(tags) AGAINST ('+tag3 +tag6 +tag4' IN BOOLEAN MODE) as score FROM items ORDER BY score DESC;
+----+-------------+----------------+-------+
| id | description | tags | score |
+----+-------------+----------------+-------+
| 5 | the fifth | tag4 tag3 tag6 | 1 |
| 1 | the first | tag1 tag3 tag4 | 0 |
| 2 | the second | tag5 tag1 tag2 | 0 |
| 3 | the third | tag5 tag1 tag9 | 0 |
| 4 | the fourth | tag5 tag6 tag2 | 0 |
| 6 | the sixth | tag2 tag3 tag6 | 0 |
+----+-------------+----------------+-------+
6 rows in set (0.00 sec)
mysql>
的解决方案似乎是评价一个布尔MODE得分，然后一个非布尔模式得分如下：
SELECT *,
MATCH(tags) AGAINST ('tag3 tag6 tag4') as score1,
MATCH(tags) AGAINST ('+tag3 +tag6 +tag4' IN BOOLEAN MODE) as score2
FROM items ORDER BY score2 DESC, score1 DESC;
这是对你的样本数据的结果：
mysql> SELECT *,
-> MATCH(tags) AGAINST ('tag3 tag6 tag4') as score1,
-> MATCH(tags) AGAINST ('+tag3 +tag6 +tag4' IN BOOLEAN MODE) as score2
-> FROM items ORDER BY score2 DESC, score1 DESC;
+----+-------------+----------------+--------------------+--------+
| id | description | tags | score1 | score2 |
+----+-------------+----------------+--------------------+--------+
| 5 | the fifth | tag4 tag3 tag6 | 0.6700310707092285 | 1 |
| 1 | the first | tag1 tag3 tag4 | 0.6700310707092285 | 0 |
| 2 | the second | tag5 tag1 tag2 | 0 | 0 |
| 3 | the third | tag5 tag1 tag9 | 0 | 0 |
| 4 | the fourth | tag5 tag6 tag2 | 0 | 0 |
| 6 | the sixth | tag2 tag3 tag6 | 0 | 0 |
+----+-------------+----------------+--------------------+--------+
6 rows in set (0.00 sec)
mysql>
或者你可以尝试不使用加号
mysql> SELECT *,
-> MATCH(tags) AGAINST ('tag3 tag6 tag4') as score1,
-> MATCH(tags) AGAINST ('tag3 tag6 tag4' IN BOOLEAN MODE) as score2
-> FROM items ORDER BY score2 DESC, score1 DESC;
+----+-------------+----------------+--------------------+--------+
| id | description | tags | score1 | score2 |
+----+-------------+----------------+--------------------+--------+
| 5 | the fifth | tag4 tag3 tag6 | 0.6700310707092285 | 3 |
| 1 | the first | tag1 tag3 tag4 | 0.6700310707092285 | 2 |
| 6 | the sixth | tag2 tag3 tag6 | 0 | 2 |
| 4 | the fourth | tag5 tag6 tag2 | 0 | 1 |
| 2 | the second | tag5 tag1 tag2 | 0 | 0 |
| 3 | the third | tag5 tag1 tag9 | 0 | 0 |
+----+-------------+----------------+--------------------+--------+
6 rows in set (0.00 sec)
mysql>
无论采用哪种方式，您都必须同时包含BOOLEAN MODE和非BOOLEAN模式。
如果您要查询的代码是以图片而不是文本形式显示的，那么对于回答者而言，您会更难。这意味着我们必须重新输入它 - 脖子上的痛苦。 –