问题一、idea中db navigator插件 The driver has not received any packets from the server或者是database对话框java.net.ConnectException: Connection refused: connect.

DB browser对话框中错误提示：Cannot connect to “Connection”.
Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

database对话框java.net.ConnectException: Connection refused: connect.

原因：The driver has not received any packets from the server.
意思是驱动程序没有收到来自服务器的任何数据包。也就是没有开启mysql数据库。java.net.ConnectException: Connection refused: connect.这个也是数据库连接有问题
解决方法：用datagrip工具也可以如此解决

问题二、如果怀疑是驱动问题就去官网下载mysql连接包

如下图，选择下载好的驱动jar包即可连接成功
具体参考https://developer.aliyun.com/article/934533

问题三、database对话框：Server returns invalid timezone. Go to ‘Advanced’ tab and set ‘serverTimezone’ property manually.

原因：Go to ‘Advanced’ tab and set ‘serverTimezone’ property manually.意思是进入“Advanced”选项卡，手动设置“serverTimezone”属性。
解决办法：
1、时区问题可以直接在URL后面添加?serverTimezone=Asia/Shanghai
2、Advanced选项卡，手动设置“serverTimezone”属性为Asia/Shanghai

来源地址：https://blog.csdn.net/qq_43290655/article/details/126296389