sql 橫向顯示

SELECT id_num, MAX(score_chinese) AS '國文成績', MAX(score_english) AS '英文成績', MAX(score_math) AS '數學成績'
FROM(
SELECT id_num,
CASE WHEN subject='國文' THEN score END AS score_chinese,
CASE WHEN subject='英文' THEN score END AS score_english,
CASE WHEN subject='數學' THEN scree END AS score_math
FROM score_table
) AS score_table_tmp
GROUP BY id_num