Database: activity_1

Question: Show the ids for all the students who participate in an activity and are under 20.
SQL: SELECT StuID FROM Participates_in INTERSECT SELECT StuID FROM Student WHERE age  <  20

Question: What is the first and last name of the student participating in the most activities?
SQL: SELECT T1.fname ,  T1.lname FROM Student AS T1 JOIN Participates_in AS T2 ON T1.StuID  =  T2.StuID GROUP BY T1.StuID ORDER BY count(*) DESC LIMIT 1

Question: What is the name of the activity with the most students?
SQL: SELECT T1.activity_name FROM Activity AS T1 JOIN Participates_in AS T2 ON T1.actID  =  T2.actID GROUP BY T1.actID ORDER BY count(*) DESC LIMIT 1

Question: Find the first names of the faculty members who are playing Canoeing or Kayaking.
SQL: SELECT DISTINCT T1.fname FROM Faculty AS T1 JOIN Faculty_participates_in AS T2 ON T1.facID  =  T2.facID JOIN activity AS T3 ON T2.actid  =  T2.actid WHERE T3.activity_name  =  'Canoeing' OR T3.activity_name  =  'Kayaking'

Question: Find the first names of professors who are not playing Canoeing or Kayaking.
SQL: SELECT fname FROM faculty WHERE rank  =  'Professor' EXCEPT SELECT DISTINCT T1.fname FROM Faculty AS T1 JOIN Faculty_participates_in AS T2 ON T1.facID  =  T2.facID JOIN activity AS T3 ON T2.actid  =  T2.actid WHERE T3.activity_name  =  'Canoeing' OR T3.activity_name  =  'Kayaking'

Question: Find the first names of the faculty members who participate in Canoeing and Kayaking.
SQL: SELECT T1.fname FROM Faculty AS T1 JOIN Faculty_participates_in AS T2 ON T1.facID  =  T2.facID JOIN activity AS T3 ON T2.actid  =  T2.actid WHERE T3.activity_name  =  'Canoeing' INTERSECT SELECT T1.fname FROM Faculty AS T1 JOIN Faculty_participates_in AS T2 ON T1.facID  =  T2.facID JOIN activity AS T3 ON T2.actid  =  T2.actid WHERE T3.activity_name  =  'Kayaking'