Isn't it hard to use two DBMSs in a BOXED script?

Question

Database

There is for example a box script of the Catalog. There, some of the data is strictly structured, and some is weakly structured. Ideally, it begs to use two DBMS. One RDBMS and one NoSQL. However, these are troubles with the settings of the second one, right? But in the boxed version (oriented to small projects), simplicity is important - you just clicked the installation, and that's it.
Considering that all this should be installed easily and work on a regular Hosting

Answer 1

Do not mind it. As part of a boxed solution - will not work.
But pay attention - a database built on files works no slower than NoSQL on a not very large amount of data. Probably up to a megabyte. Test it.

Answer 2

Let the shareds die, calmly take Postgres for nosql

Answer 3

as if the fact that there are no links in NoSQL prevents it from being used to store structured data.
On the contrary, a simple query will come out instead of all these JOINs.