By Vicent Martí | March 20, 2025The SQL evaluation engine that ships with Vitess, the open-source database that powers PlanetScale, was originally implemented as an AST evaluator that used to operate directly on the SQL AST generated by our parser. Over this past year, we've gradually replaced it with a Virtual Machine which, despite being written natively in Go, performs similarly to the original C++ evaluation code in MySQL. Most remarkably, the new Virtual Machine has repeatedly proven itself...