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CREATE TABLE mytable
([Year] int, [Month] int, [Active_Users] int)
;
INSERT INTO mytable
([Year], [Month], [Active_Users])
VALUES
(2022, 1, 123),
(2022, 2, 143),
(2022, 12, 100),
(2023, 1, 79),
(2023, 2, 3)
;
5 rows affected
SELECT YEAR,Month
, CASE WHEN Month = 12 THEN Active_users + (SELECT SUM(Active_users) FROM mytable WHERE YEAR = 2023 AND Month IN (1,2))
ELSE Active_users END Active_users
FROM mytable
WHERe YEAR = 2022
| YEAR | Month | Active_users |
|---|---|---|
| 2022 | 1 | 123 |
| 2022 | 2 | 143 |
| 2022 | 12 | 182 |