Documented database DDL statements and ordering

[dvasdekis]

Using this kit, I found it initially difficult to understand what all these DDL and schemas did, given the sequential nested hierarchy. This doco hopefully makes it easier for whoever comes after me.

[ruslantalpa]

thank you for this PR, I am on the fence with it for the following reasons (though I agree anything is better than nothing):

• I would like to have the documentation in one place and not spread around in different repositories (since there are more then one component that makes up the system)

• While this is good info, it's structured as "your understanding" of what's going on, and as documentation it would need a bit of cleanup, and I don't want to request of you to start cleaning up and tailor this to what I think it should be :).

My question is: When you had trouble understanding what's going one (and what each file/dir in here is about) is it because you did not find the following documentation (https://docs.subzero.cloud/architecture-and-project-structure/#postgresql-db and https://github.com/subzerocloud/postgrest-starter-kit#directory-layout) or was it not enough?

Thank you

[dvasdekis]

Good questions! Thanks for considering the PR.

I did find that documentation and it was useful, but as a DBA, I start every project by understanding the code running in my database before adding to it. In Postgrest, with the database as the "source of all truths", I think it's doubly important to understand what functions, tables, permissions etc. exist and why, especially when building a project that might have a public-facing API URL.

I know that it's "my understanding" of what's going on, but I'm happy to amend this with your "developer truths" if you'd like to provide them. :)