You may be looking at highly scaled distributed databases with thousands of concurrent users.
What about the base case of one large dataset being scanned linearly or by complex joins.
In its basic form an RDBMS table is like an array of structs, other types of DBs are like lists.
You wont see much performance difference in normal applications, but when there is lots of work to be done RDBMS will shine.
You may be looking at highly scaled distributed databases with thousands of concurrent users.
What about the base case of one large dataset being scanned linearly or by complex joins. In its basic form an RDBMS table is like an array of structs, other types of DBs are like lists.
You wont see much performance difference in normal applications, but when there is lots of work to be done RDBMS will shine.