modifier的值为in boolean mode的时候，可以使用布尔全文检索。在布尔全文检索中，有些字符在检索字符串的开头或结尾会有特殊含义。
在下面的示例中，+和-操作符表明在匹配的时候，单词必须存在和不存在。所以是检索含有"MySQL"但是不含有"YourSQL"的行。
mysql> SELECT
-> *
-> FROM
-> articles
-> WHERE
-> MATCH (title , body) AGAINST ('+MySQL -YourSQL' IN BOOLEAN MODE);
+----+-----------------------+-------------------------------------+
| id | title | body |
+----+-----------------------+-------------------------------------+
| 6 | MySQL Security | When configured properly, MySQL ... |
| 1 | MySQL Tutorial | DBMS stands for DataBase ... |
| 2 | How To Use MySQL Well | After you went through a ... |
| 3 | Optimizing MySQL | In this tutorial we will show ... |
| 4 | 1001 MySQL Tricks | 1. Never run mysqld as root. 2. ... |
+----+-----------------------+-------------------------------------+
5 rows in set (0.00 sec) mysql>
布尔全文检索的操作符：
+
表示该word必须存在
-
表示该word必须不被排除
(no operator)
表示word是可选的，如果出现，其相关性会更高
@distance
仅仅适用于innodb。测试两个或多个word出现的距离是否在distance的值之内，distance的单位是word个数。
下面测试的结果是多个单词之间最远的距离要在distance之间。(和姜承饶的书结果不一致)
mysql> select * from articles where id=12;
+----+-----------------+--------------------------------------------------------------+
| id | title | body |
+----+-----------------+--------------------------------------------------------------+
| 12 | BOOLEN Tutorial | word1,word2,word3,word4,word5,word6,word7,word8,word9,word10 |
+----+-----------------+--------------------------------------------------------------+
1 row in set (0.00 sec) mysql> SELECT * FROM articles WHERE MATCH (title , body) AGAINST ('"word2 word4 word9" @9' IN BOOLEAN MODE);
+----+-----------------+--------------------------------------------------------------+
| id | title | body |
+----+-----------------+--------------------------------------------------------------+
| 12 | BOOLEN Tutorial | word1,word2,word3,word4,word5,word6,word7,word8,word9,word10 |
+----+-----------------+--------------------------------------------------------------+
1 row in set (0.00 sec) mysql> SELECT * FROM articles WHERE MATCH (title , body) AGAINST ('"word2 word4 word9" @8' IN BOOLEAN MODE);
+----+-----------------+--------------------------------------------------------------+
| id | title | body |
+----+-----------------+--------------------------------------------------------------+
| 12 | BOOLEN Tutorial | word1,word2,word3,word4,word5,word6,word7,word8,word9,word10 |
+----+-----------------+--------------------------------------------------------------+
1 row in set (0.00 sec) mysql> SELECT * FROM articles WHERE MATCH (title , body) AGAINST ('"word2 word4 word9" @7' IN BOOLEAN MODE);
Empty set (0.00 sec) mysql> SELECT * FROM articles WHERE MATCH (title , body) AGAINST ('"word2 word4 word9" @6' IN BOOLEAN MODE);
Empty set (0.00 sec) mysql>
>
表示出现该单词时增加相关性
<
表示出现该单词时降低相关性
( )
子表达式
~
表示允许出现该单词，但是出现时相关性为负
*
表示以该单词开头的单词，如lik*表示lik、like等
”
匹配双引号中的字面值，全文检索引擎会将双引号中的内容按照单词分开，非单词字符不用匹配，比如"test phrase"匹配"test,phrase"