return db:add($MariaBase, $doc, $db) results in my database in Relational -> Innovate/1 -> Innovate/1 -> Dienst/1 -> row/n (1 and n indicate parity)
Sorry, I can’t follow (e.g., I don’t understand what /1 is supposed to indicate, what you mean by "indicate parity", …).
With your query, you seem to add a single document into your database that contains the contents of all tables. That’s fine in general; but is it what you are trying to achieve, or would it probably be better to represent a single table as document?
According to the documentation ommitting the third parameter in db:add should be allowed, or did I misinterpret something?
The third argument can only be omitted if the second argument points to a file or directory [1], as the name of the addressed file will then be used as database path.