Need help with this fromula

Hi Anonymous ，

For the problem you are experiencing, the use of temporary tables can solve your needs. Temporary tables can be used to dynamically adjust quantities and calculate new price values without changing the original data.

Below is an example of my data that I hope will help you.

1.declaration of percentage change variables, e.g., 5 per cent increase

DECLARE @percentage_change DECIMAL(5, 2) = 0.05;

2.Creation of temporary tables to adjust quantities

CREATE TABLE #adjusted_records (
   id INT,
   adjusted_quantity DECIMAL(10, 2),
   category INT,
   month INT
);

 3.Insert the adjusted data into the temporary table

INSERT INTO #adjusted_records (id, adjusted_quantity, category, month)
SELECT
   id,
   quantity * (1 + @percentage_change),
   category,
   month
FROM
   records;

4.Use the temporary table to calculate the new values and summarize

WITH computed_values AS (
   SELECT
       ar.id,
       ar.adjusted_quantity,
       pe.price,
       (ar.adjusted_quantity * pe.price) AS new_value
   FROM
       #adjusted_records ar
   JOIN
       price_entry pe
   ON
       ar.month = pe.month AND ar.category = pe.category
)
SELECT
   SUM(new_value) AS total_sum
FROM
   computed_values;
-- Drop the temporary table
DROP TABLE #adjusted_records;

If you have any other questions, I've found the following document to help you out, and I hope it helps.

Temporal tables - SQL Server | Microsoft Learn

Hope it helps!

Best regards,
Community Support Team_ Tom Shen

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