Just a heads up that I added initial support for UPDATE/DELETE statements this weekend. I am not happy with the way the "root from element" is modeled in UPDATE/DELETE statements, and especially the wide difference with how they work with SelectStatement and FromClause. I plan to do some more work there. I think part of that is to move away from using a concrete FromClause as the base for the "stack", instead leveraging a contract more like FromElementSpace and something like a FromElementContainer (FromClause would be one such container, so would a UpdateStatement and a DeleteStatement). Still brainstorming the specifics at the moment.