Illegal mix of collations(utf8mb4_general_ci,IMPLICIT)and(utf8mb4_0900_ai_ci,IMPLICIT)for operation‘

在开发过程中，调用存储过程是出现了下面的问题：

Cause: java.sql.SQLException: Illegal mix of collations(utf8mb4_general_ci,IMPLICIT)and(utf8mb4_0900_ai_ci,IMPLICIT)for operation'='ERROR:JtinyMsgThread-***Handle Event Exception: msgId=31000 infoorg.springframework.jdbc.UncategorizedSQLException: SqlMapClient operation; uncategorized SQLException for SQL []; SQL state [HY000]; error code [1267];   
The error occurred in com/lock/paymanager/model/Billrecord.xml.  
The error occurred while applying a parameter map.  
Check the swapParameters.  
Check the statement (update procedure failed).  
Cause: java.sql.SQLException: Illegal mix of collations (utf8mb4_general_ci,IMPLICIT) and (utf8mb4_0900_ai_ci,IMPLICIT) for operation '='; nested exception is com.ibatis.common.jdbc.exception.NestedSQLException:   
The error occurred in com/lock/paymanager/model/Billrecord.xml.  
The error occurred while applying a parameter map.  
Check the swapParameters.  
Check the statement (update procedure failed).  
Cause: java.sql.SQLException: Illegal mix of collations (utf8mb4_general_ci,IMPLICIT) and (utf8mb4_0900_ai_ci,IMPLICIT) for operation '='

Illegal mix of collations 非法混合排序规则（即非法混合了不同的字符集）

首先，查看当前数据库的默认编码：

show variables where Variable_name like 'collation%';

查看库的字符编码：