Comment by mr_toad
2 months ago
> just by porting SQL to your language
You make it sound like writing an SQL parser and query engine is a trivial task. Have you ever looked at the implementation of a query engine to see what’s actually involved? You can’t just ‘build on SQL’, you have to build a substantial library of functions to build SQL on top of.
Also it's not like dplyr is anything close to a "port" of SQL. You could in theory collect dplyr verbs and compile them to SQL, sure. That's what ORMs typically do, and what the Spark API does (and its descendants such as Polars).
"Porting" SQL to your language usually means inventing a new API for relational and/or tabular data access that feels ergonomic in the host language, and then either compiling it to SQL or executing it in some kind of array processing backend, or DataFusion if you're fancy like that.
dplyr straightforwardly transpiles to SQL through the dbplyr package, so it's semantically pretty close to a port, even though the syntax is a bit different (better).