What is the relationship between Kubernetes containers, Github repositories, and docker registry?

I also use the Docker registry in the Docker/Docker Composer, and I understand that it is at least essential for running container applications in production.

With Compose, this situation can be achieved because it can be built at the time of composition, but I understand that every time I build, the Docker container's portability of "handing moving things over to another environment" is not utilized.

Container: Github Repository: docker registry relationship was n:1:0.

If you're using the Build section in Composer, this may not be wrong, but I don't think the registry is exactly zero (because the base image in the Dockerfile was originally pulled from the registry).

I'm wondering if the relationship between container:Github repository:docker registry is 1:1:1, but is this understanding correct?

The correspondence between the container and the registry that manages the image is n:n, but I don't think that's always the case with the Git repository.

For example, there is an application that is

Front End - [Back End A - Back End B] - [Database A - Database B]

Assume that you are configured with services such as .At this time, DB needs to have both front-end applications and back-end applications, even if it has managed services or MySQL on its own host.

When using containers, it is common for each to act as an independent container, but sometimes it is better to separate repositories for each application if the size is large.

Therefore, I think it is difficult to generalize the relationship between Git's repository and the number of containers.

In addition, Kubernetes has a scaling concept unlike Composer.

In other words, when the backend A is under heavy load, it scales out horizontally according to the conditions.If the number of containers (called Pod in Kubernetes) is increasing due to scale-out, this is not always the same, as this number is not constant.