CREATE TABLE table_502 ("Season" TEXT, "Competition" TEXT, "Round" TEXT, "Club" TEXT, "1st leg" TEXT, "2nd leg" TEXT, "Aggregate" TEXT)

What is the competition when 2nd leg is 0 8?
SELECT "Competition" FROM table_502 WHERE "2nd leg" = '0–8'
SELECT "Competition" FROM "table_502" WHERE "2nd leg" = '0–8'