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MySQL里Create Index 能否创建主键 Primary Key_MySQL

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Release： 2016-06-01 13:19:27
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bitsCN.com MySQL里Create Index 能否创建主键 Primary Key?
答案：

不能，必须用 Alter table 创建。

MySQL一个索引列最大允许的有效长度，不是列的所有数据都被索引的

MyISAM 是 1000字节
InnoDB 是 767 字节

注意这里是字节。bitsCN.com

source：php.cn
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