你似乎需要 min() 解析函数 self-join :

select distinct t1.ID,
       min(t1.SeenAt) over (partition by t1.ID order by t1.ID) as "Start",
       t2.SeenAt as "End"
  from tab t1
  join tab t2 on t1.ID=t2.ID and t1.SeenAt<=t2.SeenAt
 order by t2.SeenAt;

演示

你可以用 lead() 以及 nvl() :

select id, min(seenat) over (partition by id) seen_start,
       nvl(lead(seenat) over (partition by id order by seenat), seenat) seen_end
  from t

演示

开始很容易 MIN 的 GROUP 结束后你需要找到最小值 SeenAt 如果你找不到，那么电流 SeenAt sql演示

SELECT "ID", 
        (SELECT MIN("SeenAt")
         FROM Table1 t2
         WHERE t1."ID" = t2."ID") as "Start",
        COALESCE(
                 (SELECT MIN("SeenAt")
                  FROM Table1 t2
                  WHERE t1."ID" = t2."ID"
                  AND t1."SeenAt" < t2."SeenAt")
                 , t1."SeenAt"
                ) as End

FROM Table1 t1

输出

| ID | START | END |
|----|-------|-----|
|  1 |    20 |  21 |
|  1 |    20 |  22 |
|  1 |    20 |  22 |
|  2 |    70 |  80 |
|  2 |    70 |  80 |