我有一个带有这样架构的测试表:
CREATE TABLE `indextest` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(10) DEFAULT NULL,
PRIMARY KEY (`id`),
KEY `idx_name` (`name`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=latin1
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这是表中的行:
mysql [localhost] {msandbox} (test) > select * from indextest;
+----+--------+
| id | name |
+----+--------+
| 3 | 111222 |
| 1 | hello |
| 2 | world |
| 4 | wow |
+----+--------+
4 rows in set (0.00 sec)
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当我针对name
带有字符串的列查询表时,它看起来不错:
mysql [localhost] {msandbox} (test) > explain select * …
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