If the question you end up wanting to ask, is "Can you make it easy to distribute writes to this store?", then SQL is a poor choice. We have had a stagnant SQL

If the question you end up wanting to ask, is "Can you make it easy to distribute writes to this store?", then SQL is a poor choice. We have had a stagnant SQL monoculture as a default choice for data, for 20 years. Given a project of with an uncertain future we are now starting to get other choices. We know that using an SQL databases will create pain. Suffering that pain in the hope that later questions may be answered less painfully, is becoming a mindful decision. Especially in startups, not the default that it has been in the enterprise world. Google seems to be a lot better at answering questions than Sybase is. Out of date, offline, full text indexing is not something SQL databases do well. For content like movies, music and large documents, we simply don't (and should not) create a relational model, we use big blobs and dump them into whatever tools we have around. We all would agree that if your data looks like source code you are better off with git than with MySQL. So where else does "if you don't know use SQL" breakdown.