Install MySQLDump for MySQL 8.0 on Ubuntu 18.04

To get 8.0 client tools (or server) you have to install the official MySQL repo for apt. I recommend to follow this detailed guide.

TLDR;

1. go to https://dev.mysql.com/downloads/repo/apt/
2. find the link for the latest deb package (use that in the following steps)
3. on your server:
4. wget -c https://dev.mysql.com/get/mysql-apt-config_0.8.16-1_all.deb
5. sudo dpkg -i mysql-apt-config_0.8.16-1_all.deb
6. sudo apt-get update
7. sudo apt-get install mysql-client
8. mysqldump --version (should say Ver 8.x.x)

Forget MySql packages, use MariaDb packages instead:

sudo apt-get install -y mariadb-client

https://mariadb.com/kb/en/mysqldump/