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CREATE TABLE mytable(
ID INTEGER NOT NULL PRIMARY KEY
,PAST_DUE_COL VARCHAR(32)
);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (1,'91 or more days pastdue');
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (2,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (3,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (4,'61-90 days past due');
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (5,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (6,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (7,'31-60 days past due');
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (8,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (9,'0-30 days past due');
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (10,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (11,NULL);
INSERT INTO mytable(ID,PAST_DUE_COL) VALUES (12,NULL);
12 rows affected
select
t.*,
max(past_due_col) over(partition by grp) new_past_due_col
from (
select t.*, count(past_due_col) over(order by id) grp
from mytable t
) t
| ID | PAST_DUE_COL | grp | new_past_due_col |
|---|---|---|---|
| 1 | 91 or more days pastdue | 1 | 91 or more days pastdue |
| 2 | null | 1 | 91 or more days pastdue |
| 3 | null | 1 | 91 or more days pastdue |
| 4 | 61-90 days past due | 2 | 61-90 days past due |
| 5 | null | 2 | 61-90 days past due |
| 6 | null | 2 | 61-90 days past due |
| 7 | 31-60 days past due | 3 | 31-60 days past due |
| 8 | null | 3 | 31-60 days past due |
| 9 | 0-30 days past due | 4 | 0-30 days past due |
| 10 | null | 4 | 0-30 days past due |
| 11 | null | 4 | 0-30 days past due |
| 12 | null | 4 | 0-30 days past due |
Warning: Null value is eliminated by an aggregate or other SET operation.