CREATE TABLE dorm (dormid VARCHAR2)
CREATE TABLE lives_in (stuid VARCHAR2, dormid VARCHAR2)
CREATE TABLE student (fname VARCHAR2, stuid VARCHAR2)
CREATE TABLE has_amenity (dormid VARCHAR2, amenid VARCHAR2)
CREATE TABLE dorm_amenity (amenid VARCHAR2)

Find the first name of students who are living in the dorm that has most number of amenities.
SELECT T1.fname FROM student AS T1 JOIN lives_in AS T2 ON T1.stuid = T2.stuid WHERE T2.dormid IN (SELECT T2.dormid FROM dorm AS T3 JOIN has_amenity AS T4 ON T3.dormid = T4.dormid JOIN dorm_amenity AS T5 ON T4.amenid = T5.amenid GROUP BY T3.dormid ORDER BY COUNT(*) DESC LIMIT 1)
SELECT "T1"."fname" FROM "student" "T1" JOIN "lives_in" "T2" ON "T1"."stuid" = "T2"."stuid" AND "T2"."dormid" IN (SELECT "T2"."dormid" FROM "dorm" "T3" JOIN "has_amenity" "T4" ON "T3"."dormid" = "T4"."dormid" JOIN "dorm_amenity" "T5" ON "T4"."amenid" = "T5"."amenid" GROUP BY "T3"."dormid" ORDER BY COUNT(*) DESC FETCH FIRST 1 ROWS ONLY)