Do you know any commercial database with comparable level of documentation and community support?

I worked with a certain other database from a company starting with "O" and ending with "racle", and support/documentation quality was abysmal. Our support contract was quite basic, but still, it expected to be better than free alternatives.

It was very NOT.

In comparison to what? Mysql? Perhaps. Mysql is a little simpler and quicker to pick up, but one must remember, the original intent of mysql was to stop Devs from using text files for storage...

But in comparison to an enterprise solution like DB2 or Oracle? Not even close...

If you are trying to pull nosql into the argument, that is not even apples to oranges, plus with nosql, you get to retool your entire architecture.