Please take a look at my latest column for Government Computing News where I discuss the strengths and weaknesses of relational databases and describe circumstances where document databases or graph databases may actually be a better fit. Just to give you an idea, here is the unedited introduction.
One of my current projects is to review an application built by a contractor for a major federal government agency. The code relies heavily on queries and stored procedures against a relational database management system (RDBMS). These are easily the most complex I have ever seen. When technical debt accrues in your database, refactor your database design immediately, and utilize views, indexes, precomputation, and all the other goodies your RDBMS offers.
However, it may very well be that the relational paradigm, as venerable and successful as it is, is simply not the best choice for your application. There are alternative paradigms, notably document and graph databases, which are colloquially known as NoSQL databases and have their own advantages and disadvantages. Let’s remind ourselves why RDBMS’s have dominated for so long before exploring how NoSQL databases compare.
You can read the rest of the column here.