Unknown initial character set index '45' received from server

异常信息

Unknown initial character set index '45' received from server. 
Initial client character set can be forced via the 'chara

分析

出现这个数据库连接异常，可能是你们数据库太新，所以更新一下JDBC连接驱动，原来的是5.0.4 ，现在换成5.1.47.连接成功。
进入数据库,命令行输入mysql -u root -p，回车输入密码。

MariaDB [(none)]> status;
--------------
mysql  Ver 15.1 Distrib 10.1.37-MariaDB, 
for debian-linux-gnu (x86_64) using readline 5.2

Connection id:		115
Current database:	
Current user:		zzyy@localhost
SSL:			Not in use
Current pager:		stdout
Using outfile:		''
Using delimiter:	;
Server:			MariaDB
Server version:		10.1.37-MariaDB-0+deb9u1 Debian 9.6
Protocol version:	10
Connection:		Localhost via UNIX socket
Server characterset:	utf8mb4
Db     characterset:	utf8mb4
Client characterset:	utf8mb4
Conn.  characterset:	utf8mb4
UNIX socket:		/var/run/mysqld/mysqld.sock
Uptime:			51 min 26 sec

Threads: 3  Questions: 51  
Slow queries: 0  Opens: 19  Flush tables: 1  
Open tables: 13  Queries per second avg: 0.016
--------------

解决方案

更新JAR包

<dependency>
	<groupId>mysql</groupId>
	<artifactId>mysql-connector-java</artifactId>
	<version>5.0.4</version>
</dependency>

更新为

<dependency>
	<groupId>mysql</groupId>
	<artifactId>mysql-connector-java</artifactId>
	<version>5.1.47</version>
</dependency>

maven clean install

执行mvn clean install命令。