MySql修改或者创建索引是的错误提示:ERROR 1170 (42000): BLOB/T

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MySql修改或者创建索引是的错误提示:ERROR 1170 (42000): BLOB/T_MySQL

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Jun 01, 2016 pm 01:30 PM

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MySql修改或者创建索引是的错误提示:ERROR 1170 (42000): BLOB/T...解决

在创建或修改mysql索引时出现了这样的错误：

ERROR 1170 (42000): BLOB/TEXT column 'col2' used in key specification without a key length

看了下该表的数据结构发现col2字段类型是text ,查询了下发现是：

MySQL只能将BLOB/TEXT类型字段设置索引为BLOB/TEXT数据的钱N个字符.

索引指定下col2的长度就可以了：

alter table foo add index col_2 (col2(10))

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