Find nested data SQL Server? [closed] - sql-server

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I have a table with promo sales, but some promos last a different amount of time.
+---------+-------------+---------+----------+------------+-----+
| year_id | week_number | good_id | store_id | promo_name | qty |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 41 | 22197 | 64 | October | 10 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 42 | 22197 | 64 | October | 2 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 43 | 22197 | 64 | October | 54 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 44 | 22197 | 64 | October | 3 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 41 | 22197 | 64 | Flash | 13 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 42 | 22197 | 64 | Flash | 56 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 42 | 22197 | 64 | New | 41 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 43 | 22197 | 64 | New | 4 |
+---------+-------------+---------+----------+------------+-----+
I would like to find for each pair of good-store all such cases where shorter promos go into longer ones and change their name, for example:
+---------+-------------+---------+----------+------------+-----+
| year_id | week_number | good_id | store_id | promo_name | qty |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 41 | 22197 | 64 | October | 10 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 42 | 22197 | 64 | October | 2 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 43 | 22197 | 64 | October | 54 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 44 | 22197 | 64 | October | 3 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 41 | 22197 | 64 | October | 13 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 42 | 22197 | 64 | October | 56 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 42 | 22197 | 64 | October | 41 |
+---------+-------------+---------+----------+------------+-----+
| 2019 | 43 | 22197 | 64 | October | 4 |
+---------+-------------+---------+----------+------------+-----+

Answer 1

For the first value of promo_name when sorted by year & week for the same good_id & store_id
Then the FIRST_VALUE window function would be my pick.
SELECT year_id, week_number, good_id, store_id,
FIRST_VALUE(promo_name) OVER (PARTITION BY good_id, store_id ORDER BY year_id, week_number) AS promo_name,
qty
FROM PromoSales ps
ORDER BY 1, 2, 3, 4
To use it in an update
WITH CTE AS
(
SELECT
promo_name,
FIRST_VALUE(promo_name) OVER (PARTITION BY good_id, store_id ORDER BY year_id, week_number) AS original_promo_name
FROM PromoSales
)
UPDATE CTE
SET promo_name = original_promo_name
WHERE promo_name != original_promo_name
AND original_promo_name IS NOT NULL;