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文章摘要

这篇文章描述了一种MySQL数据库连接错误，主要错误类型为`com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Unsupported command`，并提示在SQL语句中存在不支持的命令或语法问题。错误可能与配置文件中的参数映射表（如`mapper/XXXXXXXXX-Mapper.xml`或`mapper/XXXXXXXXXOMapper.xml`）设置或SQL语句中的命令不兼容有关。文章建议检查SQL语句中的语法问题，确保所有命令都被支持，并验证配置文件中的参数映射表设置是否正确。

### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Unsupported command
### The error may exist in class path resource [mapper/XXXXXXXXX-Mapper.xml]
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: select t3.cino, t2.sn as orderSn, t2.provider_id as providerId, t4.logistics_no as logisticsSn, t2.`name`,
### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Unsupported command
; Unsupported command; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Unsupported command
org.springframework.dao.DataAccessResourceFailureException:
### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Unsupported command
### The error may exist in class path resource [mapper/XXXXXXXXXOMapper.xml]
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: select t3.cino, t2.sn as orderSn, t2.provider_id as providerId, t4.logistics_no as logisticsSn,
### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Unsupported command