SQL has a lot of incidental, accidental complexity, no doubt. Though when I reason about SQL, I think mostly in terms of functional operators over streams of d

SQL has a lot of incidental, accidental complexity, no doubt. Though when I reason about SQL, I think mostly in terms of functional operators over streams of data: projection, filtering, flat-map, join, fold/reduce. Obviously optimization means looking through streams and seeing tables to find indexes etc., but once you get to the execution plan, you're firmly in a concrete world of data flow and streams of tuples. I didn't get on well with the example syntax in this write-up. It didn't mesh better with my mental model of relational algebra either at the logical or physical execution level - and the truth is you need a foot in both worlds to write good scalable SQL today. Aside from the complexities of dynamic construction, my biggest problem with SQL is modal changes in query plans, owing to how declarative it is. It's a two-edged sword: the smart planner is great, up until it's stupid. And it usually turns stupid based on index statistics in production at random times.