Override root default superuser name

[metametadata]

Would be great to have something like MYSQL_ROOT_USER environment variable to change the default root superuser name.

E.g. PostgreSQL (https://hub.docker.com/_/postgres) has POSTGRES_USER for that.

[LaurentGoderre]

I can't find this usecase in the MySQL documentation. It's possible that it isn't meant to be configurable.

[tianon]

I'm going to close for now; if we can find documentation for how to do this in a supported way, we can reopen. 👍

[metametadata]

Can't the Docker container simply execute a query? E.g. from https://stackoverflow.com/a/19539029/4839573:

use mysql;
update user set user='admin' where user='root';
flush privileges;

[tianon]

It sure could, but then it might as well be dropped into /docker-entrypoint-initdb.d by users instead (and there's not a compelling reason for us to add explicit code for this). 😅

[tianon]

To put that another way, we've already got more behavior we've "invented" on top of a stock MySQL experience than we're comfortable with, so anything that doesn't have to be extra behavior invented by (and maintained by) us is good, and the thing that would make this compelling for us is if it could be done pre-initialization such that the database never has a root user to begin with. Without that, I'm afraid this isn't something we're willing to support/maintain officially.

[metametadata]

I see, thanks! FWIW, I run containers programmatically and all the user name consts are defined in Clojure code. So for me as a consumer, it's more hassle to set up /docker-entrypoint-initdb.d to change the user name than to pass the env var.