1.Cannot create PoolableConnectionFactory (Client does not support authentication protocol requested by server; consider upgrading MySQL client)
原因：jar包比数据库版本低，楼主用的数据库是MySQL 8.0.12，而jdbc是mysql-connector-java-5.1.7-bin.jar
解决方法：删除现有的jar包，重新导入新的jar包(楼主下的是对应于MySQL 8.0.12的jar包：mysql-connector-java-8.0.12.jar)
下面是MySQL jdbc(即jar包)驱动的下载链接：
下载链接（官网）：https://dev.mysql.com/downloads/connector/j/
下载链接（包含各个版本的mysql jdbc的驱动）：http://central.maven.org/maven2/mysql/mysql-connector-java/
下载链接:https://mvnrepository.com/artifact/mysql/mysql-connector-java
2. Cannot create PoolableConnectionFactory (The server time zone value '???��������??��??' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.)
原因：时间无法识别
解决方法：在连接mysql的url后添加：？serverTimezone=UTC
补充说明：UTC（格林威治时间坐标）
3.jmeter链接MySQL的方法