CREATE TABLE people (people_id DECIMAL, name TEXT, age DECIMAL, height DECIMAL, hometown TEXT)
CREATE TABLE gymnast (gymnast_id DECIMAL, floor_exercise_points DECIMAL, pommel_horse_points DECIMAL, rings_points DECIMAL, vault_points DECIMAL, parallel_bars_points DECIMAL, horizontal_bar_points DECIMAL, total_points DECIMAL)

List the names of gymnasts in ascending order by their heights.
SELECT T2.name FROM gymnast AS T1 JOIN people AS T2 ON T1.gymnast_id = T2.people_id ORDER BY T2.height
SELECT "T2"."name" FROM "gymnast" AS "T1" JOIN "people" AS "T2" ON "T1"."gymnast_id" = "T2"."people_id" ORDER BY "T2"."height" NULLS FIRST