Presto/SQL 查找下一个满足条件的值

Question

我有一个 table 如下所示，前 3 列是原始 table，最后 2 列是我想要的。所以我想要的是：

如果 "issued" 事件发生
如果发生"issued"，"issued"

我能够通过将原始 table 中的 "issued" 替换为 1 并使用自连接并将 "replaced issued" 与 sum(case when t2.event_ts between t1.event_ts and date_add('day',30,t1.event_ts) then t2.issued end) as issued_in_month 求和来确定是否已发布。

但我不确定如何获取 "issued" 时间戳。

如何在 Presto 中执行此操作？谢谢

| event_id                         | event_ts      | event_name | issued_within_30_days | issued_ts     |
|----------------------------------|---------------|------------|-----------------------|---------------|
| fc25df28c8bb188e8d15c1fea4acd06a | 6/1/18 21:31  | CLICK      | 1                     | 6/27/18 10:18 |
| 2b48d5ea80829cdd1014a68631160eb0 | 6/6/18 17:25  | OPEN       | 1                     | 6/27/18 10:18 |
| f4f6d9af7217031e5579c6d741fe3d21 | 6/8/18 0:00   | MAIL_DROP  | 1                     | 6/27/18 10:18 |
| 4a5af238e28688bf899def0905210550 | 6/10/18 4:25  | OPEN       | 1                     | 6/27/18 10:18 |
| a7945e7087c27d7f6bd7c66a397bf6bf | 6/25/18 17:53 | CLICK      | 1                     | 6/27/18 10:18 |
| 82eba7f62a9398347d67073291547765 | 6/27/18 4:58  | OPEN       | 1                     | 6/27/18 10:18 |
| 6d6984822e98009a0a30deda1204a5e0 | 6/27/18 4:58  | CLICK      | 1                     | 6/27/18 10:18 |
| 6229316a4ebcb56124e1180c9e2f60be | 6/27/18 10:18 | ISSUED     | 1                     | 6/27/18 10:18 |
| 3994ed57abc330e16965f13a2a37edd8 | 6/27/18 11:19 | SEND       | 0                     |               |
| 70f0a4d73975f26523415625309f1f64 | 7/4/18 17:30  | SEND       | 0                     |               |
| a7dd44648a0ce0029ad1ec7106fcf95c | 7/4/18 18:37  | OPEN       | 0                     |               |
| 8a823394754276a46fa3021ddc7a7290 | 7/6/18 0:00   | MAIL_DROP  | 0                     |               |
| 7a4c451554ba08da59a85a3fa61de7b6 | 7/6/18 20:18  | SEND       | 0                     |               |
| f992b7a5a25f765e5fd6f7dde129f9dc | 7/7/18 1:16   | OPEN       | 0                     |               |
| 9370e4901a4796371827e2f45862ba66 | 7/11/18 4:35  | CLICK      | 0                     |               |
| 96badd7253344f79c7ac2a47032d5942 | 2/22/19 17:20 | ISSUED     | 0                     |               |

Answer 1

最简单的方法可能是累积最小值和一些 case 表达式：

select t.*,
       (case when next_issued_ts < event_ts + interval '30' day
             then 1 else 0
        end) as issued_within_30_days,
       (case when next_issued_ts < event_ts + interval '30' day
             then next_issued_ts
        end) as issued_ts
from (select t.*,
             min(case when event = 'issued' then event_ts end) over
                 (order by event_ts desc) as next_issued_ts
      from t
     ) t

Presto/SQL 查找下一个满足条件的值

Presto/SQL find next value that meets a condition

sql

lag

window-functions

presto