当与条件字数一起使用时，全文索引在布尔模式下被忽略

Question

当我为其布尔模式添加一些有条件的单词时，全文匹配会忽略其索引。选择如下：

explain select * from seeds  WHERE  MATCH(text) AGAINST ("mount cameroon" IN BOOLEAN MODE);

输出

+----+-------------+-------+----------+---------------+------+---------+------+------+-------------+
| id | select_type | table | type     | possible_keys | key  | key_len | ref  | rows | Extra       |
+----+-------------+-------+----------+---------------+------+---------+------+------+-------------+
|  1 | SIMPLE      | seeds | fulltext | text          | text | 0       |      |    1 | Using where |
+----+-------------+-------+----------+---------------+------+---------+------+------+-------------+

具有多个单词条件

explain select * from seeds  WHERE  MATCH(text) AGAINST ("mount cameroon" IN BOOLEAN MODE) = 4;

输出

+----+-------------+-------+------+---------------+------+---------+------+------+-------------+
| id | select_type | table | type | possible_keys | key  | key_len | ref  | rows | Extra       |
+----+-------------+-------+------+---------------+------+---------+------+------+-------------+
|  1 | SIMPLE      | seeds | ALL  | NULL          | NULL | NULL    | NULL | 9607 | Using where |
+----+-------------+-------+------+---------------+------+---------+------+------+-------------+

的相同查询，这肯定不是正确的行为吗？

Answer 1

诊断结果是，当全文匹配中添加任何条件时，Mysql优化器很容易混淆。解决方案是重构查询（拆分为子查询和联接）。

此诊断和解决方案由 RolandoMySQLDBA (https://stackoverflow.com/users/491757/rolandomysqldba) 提供，并且此处提供完整内容

优化mysql全文搜索，

这里

https://dba.stackexchange.com/ questions/7136/fulltext-index-ignored-in-boolean-mode-with-number-of-words-conditional。