Breaking the language barrier

DRANK

In RavenDB 4.0, we decided to finally bite the bullet and write our own query language. That led to a lot of really complex decisions that we had to make. I already posted about the language and you saw some first drafts. RQL is meant to be instantly familiar to anyone who used SQL before.At the same time, this led to issues. In particular, the major issue is that SQL as a language is meant to handle rectangular tables, and RavenDB isn’t storing data in tables.  For that matter, we also want to give our users the ability to express themselves fully in the query language, that means support for complex queries and complex projections.For a while, we explored the option of supporting nested selects as the way to express these semantics, but that was pretty horrible, both in terms of the complexity of the implementation and in terms of the complexity of the language. Instead, we decided that take only the good parts out of SQL .What do I mean by that? Well, here is a pretty simple query…