Context: CREATE TABLE projects (code VARCHAR, name VARCHAR); CREATE TABLE scientists (name VARCHAR, SSN VARCHAR); CREATE TABLE assignedto (project VARCHAR, scientist VARCHAR)
Question: Find the name of the scientist who worked on both a project named 'Matter of Time' and a project named 'A Puzzling Parallax'.
Answer: SELECT T3.name FROM assignedto AS T1 JOIN projects AS T2 ON T1.project = T2.code JOIN scientists AS T3 ON T1.scientist = T3.SSN WHERE T2.name = 'Matter of Time' INTERSECT SELECT T3.name FROM assignedto AS T1 JOIN projects AS T2 ON T1.project = T2.code JOIN scientists AS T3 ON T1.scientist = T3.SSN WHERE T2.name = 'A Puzzling Parallax'