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SELECT * INTO #data FROM (VALUES
(CAST('2021-08-15' AS DATE), 'Bulgaria', 1081636),
('2021-08-16', 'Bulgaria', 1084693),
('2021-08-17', 'Bulgaria', 1089066),
('2021-08-18', 'Bulgaria', NULL),
('2021-08-19', 'Bulgaria', NULL),
('2021-08-20', 'Bulgaria', 1189066)) x(dt, country, cnt)
6 rows affected
SELECT dt
, country
, cnt
, MAX(cnt) OVER (PARTITION BY country ORDER BY dt)
FROM #data
ORDER BY dt
| dt | country | cnt | (No column name) |
|---|---|---|---|
| 2021-08-15 | Bulgaria | 1081636 | 1081636 |
| 2021-08-16 | Bulgaria | 1084693 | 1084693 |
| 2021-08-17 | Bulgaria | 1089066 | 1089066 |
| 2021-08-18 | Bulgaria | null | 1089066 |
| 2021-08-19 | Bulgaria | null | 1089066 |
| 2021-08-20 | Bulgaria | 1189066 | 1189066 |
Warning: Null value is eliminated by an aggregate or other SET operation.
SELECT dt
, country
, cnt
, SUM(cnt) OVER (PARTITION BY country, partition)
FROM (
SELECT country
, dt
, cnt
, SUM(CASE WHEN cnt IS NULL THEN 0 ELSE 1 END) OVER (PARTITION BY country ORDER BY dt) AS partition
FROM #data
) AS d
ORDER BY dt
| dt | country | cnt | (No column name) |
|---|---|---|---|
| 2021-08-15 | Bulgaria | 1081636 | 1081636 |
| 2021-08-16 | Bulgaria | 1084693 | 1084693 |
| 2021-08-17 | Bulgaria | 1089066 | 1089066 |
| 2021-08-18 | Bulgaria | null | 1089066 |
| 2021-08-19 | Bulgaria | null | 1089066 |
| 2021-08-20 | Bulgaria | 1189066 | 1189066 |
Warning: Null value is eliminated by an aggregate or other SET operation.