Outline of SQL tutorial has hit the "100 queries" goal <https://gvwilson.github.io/sql-tutorial/> still have at least six diagrams to draw, and would like appendices showing how to use DuckDB to do the same things (easy) and how to use permissions etc. in PostgreSQL (hard because setup and re-run). Help always welcome: please see <https://gvwilson.github.io/sql-tutorial/contributing/> for the contributors' guide.