Unknown initial character set index '255' received from server. Initial client character set can be forced via the 'characterEncoding' property.

错误：

Caused by: java.sql.SQLException: Unknown initial character set index '255' received from server. Initial client character set can be forced via the 'characterEncoding' property.
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)

原因：

 

 

 

这是编码不匹配的原因，MySQL驱动和数据库字符集设置不搭配，默认字符集已从latin1变成utf8mb4，因而系统变量受到影响

解决办法：

在后面加上这样一段代码：

<property name="url" value="jdbc:mysql://localhost:3306/eesy_mybatis?characterEncoding=utf8"/>

解决了