Developer Setup for Ubuntu

I am trying to install mattermost server on my desktop. I am following

But I am getting the error when I run

`mysqldump -h --column-statistics=0 -u mmuser -p mattermost_test mm_mysql_backup.sql` 

Error: mysqldump: [ERROR] unknown variable 'column-statistics=0'

So I removed 'column-statistics=0'

And again run the command, then it shows a password screen.

`mysqldump: Got error: 1045: Access denied for user 'mmuser'@'localhost' (using password: YES) when trying to connect`

What is the password or I am missing something here.

How to create a mmuser I just want a completely fresh installation as It is my first time installing mattermost server.