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create table sample (
id int primary key,
flag tinyint,
coluna int
);
insert into
sample
values
(1, 0, 20)
,(2, 0, 23)
,(3, 0, 40)
,(4, 1, 45)
,(5, 1, 50);
select
id,
coluna,
lag(coluna) over (order by id) as lag_coluna
from sample
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| id | coluna | lag_coluna |
|---|---|---|
| 1 | 20 | null |
| 2 | 23 | 20 |
| 3 | 40 | 23 |
| 4 | 45 | 40 |
| 5 | 50 | 45 |