I’m a beginner in data structures and algorithms, and I’m not sure how to apply them in practice to specific problems. I want to query book_name & user_id, as well as VP and UV, and I’ve used multi-layer nested subqueries. Although the logic is fine, the time complexity is too high. How should I solve this?

SELECT
  Q.book_name,
  Q.user_id,
  total_vp.VP,
  total_uv.UV
FROM 
(
SELECT*
FROM 
(
  SELECT
    user_id,
    ext_map['book_name'] AS book_name,
    ext_map['strategy_name'] AS strategy_name
  FROM
    dws.dws_clt_video_event_log_simple_hour
  WHERE
    dt = '02024060700'
  LIMIT 1000
) AS q
WHERE (q.strategy_name = 'foru-base' OR q.strategy_name = 'foru-test1')
) Q
INNER JOIN (
  SELECT
    ext_map['book_name'] AS book_name,
    COUNT(*) AS VP
  FROM
    dws.dws_clt_video_event_log_simple_hour
  GROUP BY
    ext_map['book_name']
) AS total_vp
ON Q.book_name = total_vp.book_name
INNER JOIN (
  SELECT
    ext_map['book_name'] AS book_name,
    COUNT(DISTINCT user_id) AS UV
  FROM
    dws.dws_clt_video_event_log_simple_hour
  GROUP BY
    ext_map['book_name']
) AS total_uv
ON Q.book_name = total_uv.book_name

I hope to be able to get the results within ten minutes, but I don’t know how to operate.

INFO : 2024-06-11 19:01:48,721 Stage-25_0: 45/45 Finished Stage-26_0: 1417(+8)/25125 Stage-27_0: 0/25125 Stage-28_0: 0/2199 Stage-29_0: 0/1099
INFO : 2024-06-11 19:01:49,723 Stage-25_0: 45/45 Finished Stage-26_0: 1418(+8)/25125 Stage-27_0: 0/25125 Stage-28_0: 0/2199 Stage-29_0: 0/1099