MySQL5.7 加强了在线DDL（varchar字符集）-Mysql Tutorial-php.cn

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MySQL5.7 加强了在线DDL（varchar字符集）

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Jun 07, 2016 pm 04:48 PM

在MySQL5.6引入了在线DDL，添加字段和辅助索引不锁表，但修改字段属性是锁表的。请见：http://hcymysql.blog.51cto.com/5223301/1370546如今在MySQL5.7，加强了

在MySQL5.6引入了在线DDL，添加字段和辅助索引不锁表，但修改字段属性是锁表的。请见：

如今在MySQL5.7，加强了修改varchar字段属性不锁表，例：

参考：

BTW：

MySQL5.7还支持更改索引名，不过实用性不高，谁没事闲得改索引的名字？例：

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