diff --git a/docs/queries/douyin-ads-last-7-days.sql b/docs/queries/douyin-ads-last-7-days.sql
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+-- 抖音所有账号：最近七天有没有带「广告」标签的视频
+--
+-- **每个账号一行，一个都不少** —— 包括这几天没发广告的、以及一条作品都没有的号。
+-- 有广告的：那一行带上「最新那条广告视频」的详情；没有的：只剩博主信息，作品列是空的。
+--
+-- 判定口径：
+--   * 「最近七天」看的是作品的 **published_at（作者发布时间）**，不是我们什么时候采到的。
+--     想改成「最近七天新发现的」，把两处 `n.published_at >= ...` 换成
+--     `n3.first_seen_at >= ...` / `n2.first_seen_at >= ...`。
+--   * 广告标签按**名字**匹配（`tg.name = '广告'`）。改了标签名的话这里也要跟着改。
+--     标签是全局的（不按平台分），而这里只查抖音。
+--   * 窗口下界只在**一个地方**定义（下面那个 `w` 子查询），改天数只改那一处。
+--     写成 `(UNIX_TIMESTAMP() - 7 * 86400) * 1000` 算的，**不经过时区** —— 库里存的是
+--     毫秒时间戳，和 MySQL 的 time_zone 设置无关，这样最不容易出错。
+--   * MySQL 5.7 没有窗口函数，挑「最新那条」还是用相关子查询。
+--
+-- 只想看某一个任务：把四处 `t.platform = 'dy'` 换成 `t1.id = 7` 这类条件
+-- （账号清单两处、最新广告视频子查询一处、账号快照子查询一处）。
+
+SELECT
+  acct.creator_hash                              AS 博主哈希,
+  ca.alias                                       AS 博主备注,
+  COALESCE(n.creator_name, st.nickname, '')      AS 博主昵称,
+  st.fans                                        AS 粉丝数,
+  st.total_favorited                             AS 总获赞,
+  st.works_count                                 AS 主页作品数,
+  -- 这七天里带「广告」标签的视频有几条。0 就是没有 —— 这一行的作品列会是空的。
+  (SELECT COUNT(*)
+     FROM monitor_note n3
+     JOIN monitor_task t5 ON t5.id = n3.task_id
+    WHERE t5.platform = 'dy'
+      AND n3.creator_hash = acct.creator_hash
+      AND n3.published_at >= w.since
+      AND EXISTS (SELECT 1 FROM monitor_note_tag nt
+                    JOIN monitor_tag tg ON tg.id = nt.tag_id
+                   WHERE nt.platform = 'dy'
+                     AND nt.note_id = n3.note_id
+                     AND tg.name = '广告'))         AS 近七天广告视频数,
+  n.note_id                                      AS 作品ID,
+  n.title                                        AS 作品标题,
+  n.note_url                                     AS 作品链接,
+  FROM_UNIXTIME(n.published_at / 1000)           AS 发布时间,
+  m.liked_count                                  AS 点赞,
+  m.comment_count                                AS 评论,
+  m.collected_count                              AS 收藏,
+  m.share_count                                  AS 分享,
+  (SELECT GROUP_CONCAT(t.name ORDER BY t.sort_order SEPARATOR ' / ')
+     FROM monitor_note_tag nt
+     JOIN monitor_tag t ON t.id = nt.tag_id
+    WHERE nt.platform = 'dy' AND nt.note_id = n.note_id)  AS 标签,
+  (SELECT na.alias FROM monitor_note_alias na
+    WHERE na.platform = 'dy' AND na.note_id = n.note_id LIMIT 1) AS 作品备注
+FROM
+-- 七天窗口的下界（毫秒）。**改天数只改这一行。**
+(SELECT (UNIX_TIMESTAMP() - 7 * 86400) * 1000 AS since) w
+CROSS JOIN (
+    -- 账号清单：作品里出现过的
+    SELECT n1.creator_hash
+      FROM monitor_note n1
+      JOIN monitor_task t1 ON t1.id = n1.task_id
+     WHERE t1.platform = 'dy'
+    UNION
+    -- ∪ 有账号资料的（包含一条作品都没有的博主）
+    SELECT s1.creator_hash
+      FROM monitor_creator_stat s1
+      JOIN monitor_task t2 ON t2.id = s1.task_id
+     WHERE t2.platform = 'dy'
+) acct
+-- 这七天里最新的一条**带广告标签的**作品。没有就整块为空 —— 但博主那几列照常显示。
+LEFT JOIN monitor_note n
+       ON n.id = (SELECT n2.id
+                    FROM monitor_note n2
+                    JOIN monitor_task t3 ON t3.id = n2.task_id
+                   WHERE t3.platform = 'dy'
+                     AND n2.creator_hash = acct.creator_hash
+                     AND n2.published_at >= w.since
+                     AND EXISTS (SELECT 1 FROM monitor_note_tag nt2
+                                   JOIN monitor_tag tg2 ON tg2.id = nt2.tag_id
+                                  WHERE nt2.platform = 'dy'
+                                    AND nt2.note_id = n2.note_id
+                                    AND tg2.name = '广告')
+                   ORDER BY n2.published_at DESC, n2.id DESC
+                   LIMIT 1)
+-- 那条作品最近一轮的指标
+LEFT JOIN monitor_note_metric m
+       ON m.id = (SELECT m2.id
+                    FROM monitor_note_metric m2
+                   WHERE m2.task_id = n.task_id
+                     AND m2.note_id = n.note_id
+                   ORDER BY m2.run_id DESC
+                   LIMIT 1)
+LEFT JOIN monitor_creator_alias ca
+       ON ca.platform = 'dy' AND ca.creator_hash = acct.creator_hash
+-- 博主最近一轮的账号级指标
+LEFT JOIN monitor_creator_stat st
+       ON st.id = (SELECT s2.id
+                     FROM monitor_creator_stat s2
+                     JOIN monitor_task t4 ON t4.id = s2.task_id
+                    WHERE t4.platform = 'dy'
+                      AND s2.creator_hash = acct.creator_hash
+                    ORDER BY s2.run_id DESC
+                    LIMIT 1)
+-- 有广告的排前面（数量降序），其余按粉丝数
+ORDER BY 近七天广告视频数 DESC, st.fans DESC, acct.creator_hash