CREATE TABLE table_203_502 (id DECIMAL, "team" TEXT, "titles" DECIMAL, "runner-up" DECIMAL, "third place" DECIMAL, "fourth place" DECIMAL, "years participated" DECIMAL)

which school has participated the longest number of years ?
SELECT "team" FROM table_203_502 ORDER BY "years participated" DESC LIMIT 1
SELECT "team" FROM "table_203_502" ORDER BY "years participated" DESC NULLS LAST LIMIT 1