Why We Eliminated the Primary Key B+Tree

Every database has a primary key index, and almost every one of them is a tree. Typhon's was too — until we noticed that nothing had ever asked it for a key in order. A query in this engine can only filter on an indexed component field, and an entity id is not one, so the primary key was doing exact-match lookups and nothing else. This is what a B+Tree charges you for ordering, and what happens…