我是在ubuntu 20.04中安装mysql时遇到错误如下：
The following packages have unmet dependencies:
mysql-community-client-plugins : Depends: libssl1.1 (>= 1.1.1) but 1.1.0g-2ubuntu4 is to be installed
E: Unable to correct problems, you have held broken packages.
可能是我不小心使用命令行卸载了
apt remove libmysqlclient21:amd64
这个时候需要手动安装libssl。可以参考：https://blog.csdn.net/weixin_40932028/article/details/109580216
官网地址：https://packages.ubuntu.com/bionic/amd64/libssl1.1/download
wget http://security.ubuntu.com/ubuntu/pool/main/o/openssl/libssl1.1_1.1.1-1ubuntu2.1~18.04.20_amd64.deb
sudo dpkg -i libssl1.1_1.1.1-1ubuntu2.1~18.04.20_amd64.deb
