CREATE TABLE table_203_593 (id DECIMAL, "tenure" TEXT, "coach" TEXT, "years" DECIMAL, "record" TEXT, "pct." DECIMAL, "ncaa tournament" DECIMAL)

who was the first coach to reach the ncaa tournament ?
SELECT "coach" FROM table_203_593 WHERE NOT "ncaa tournament" IS NULL ORDER BY "tenure" LIMIT 1
SELECT "coach" FROM "table_203_593" WHERE NOT "ncaa tournament" IS NULL ORDER BY "tenure" NULLS FIRST LIMIT 1