Atlas data structure: columnar NoSQL for Kerf
Kerf introduces a new data structure called an “Atlas” that we think is a helpful thing to have inside of a programming language. We’ve found it very useful to have database Tables inside of a programming language, and the Atlas concept is a natural extension of that. Be careful about jumping to conclusions, though, since an Atlas does a few special things that make it unlike what you might expect. I’ll give a preview of the major points here:
Responds to SQL
First-class language type
We didn’t spend much time talking about Atlases originally, because interest in NoSQL-style computation seemed to be on the wane. Recently, however, we’ve had a lot of requests for those sorts of applications, and so a detailed description seems in order. (If you’ve come across any interesting problems like that in your work, tell us about them.)
If a Table is a way of including a SQL table inside of the language, then an Atlas is a way of including a NoSQL store: none of the rows have to have the same columns. In other words, an Atlas is a schemaless table. The Atlas is a generalization of the Table where the rows don’t have to be uniform. In one sense, an Atlas is a sparse Table. You could also think of a Table as a vectorized Atlas.