CREATE TABLE projects (code TEXT, name TEXT, hours DECIMAL)
CREATE TABLE scientists (ssn DECIMAL, name TEXT)
CREATE TABLE assignedto (scientist DECIMAL, project TEXT)

What are the names of scientists who have not been assigned a project?
SELECT name FROM scientists WHERE NOT ssn IN (SELECT scientist FROM assignedto)
SELECT "name" FROM "scientists" WHERE NOT "ssn" IN (SELECT "scientist" FROM "assignedto")