CREATE TABLE table_204_489 (id DECIMAL, "rank" DECIMAL, "name" TEXT, "height" TEXT, "floors" DECIMAL, "year" DECIMAL, "notes" TEXT)

how tall -lrb- in meters -rrb- is the tallest building ?
SELECT "height" FROM table_204_489 ORDER BY "height" DESC LIMIT 1
SELECT "height" FROM "table_204_489" ORDER BY "height" DESC NULLS LAST LIMIT 1