CREATE TABLE TRACK (GenreId VARCHAR2)
CREATE TABLE GENRE (Name VARCHAR2, GenreId VARCHAR2)

What is the name of the most common genre in all tracks?
SELECT T1.Name FROM GENRE AS T1 JOIN TRACK AS T2 ON T1.GenreId = T2.GenreId GROUP BY T2.GenreId ORDER BY COUNT(*) DESC LIMIT 1
SELECT "T1"."Name" FROM "GENRE" "T1" JOIN "TRACK" "T2" ON "T1"."GenreId" = "T2"."GenreId" GROUP BY "T2"."GenreId" ORDER BY COUNT(*) DESC FETCH FIRST 1 ROWS ONLY