Update table from table with multiple rows of data - mysql

Question

I have a function with several product ID's in a table. I want to perform this update and set these variables to the desired product ID's. Right now, this updates only the first productID from my function that splits the multiple values of my variable. I'm aware a CTE would be ideal here, but I'm not great at the syntax.
My desired outcome is for each value in #CSV, execute the update statement. Any assistance would be great.
DECLARE
#MaxAllowance INT = 25,
#AllowanceType INT = 2,
#AllowancePeriod INT = 2,
#Account_ID INT = 13379,
#CSV VARCHAR(50) = '506,280,281,282,286',
#count INT
DECLARE #DiscountClass_ID INT =
(
SELECT DiscountClass_ID FROM Account WHERE Account_ID = #Account_ID
);
SELECT #count =
(
SELECT COUNT(*) FROM dbo.FN_csv_tolist(#CSV)
);
declare #ProductID int
declare #rn int
declare ItemCursor cursor local static forward_only read_only for
select Value,
row_number() over(partition by Value order by Value) as rn
FROM dbo.FN_csv_tolist(#CSV)
open ItemCursor
fetch next from ItemCursor
into #ProductID, #rn
WHILE #count > 0
begin
update dbo.ProdTerm
SET MaxAllowance = #MaxAllowance,
AllowanceType = #AllowanceType,
AllowancePeriod = #AllowancePeriod
WHERE Product_ID = #ProductID
SET #count = #count - 1;
fetch next from ItemCursor
into #ProductID, #rn
end
close ItemCursor
deallocate ItemCursor

Answer 1

I am a little confused by your code, I am not sure of the reason for the need of a cursor, as the code could be a lot simpler. One way would be:
DECLARE #MaxAllowance INT = 25,
#AllowanceType INT = 2,
#AllowancePeriod INT = 2,
#CSV VARCHAR(50) = '506,280,281,282,286';
WITH Test
AS
(
SELECT [Value]
FROM dbo.FN_csv_tolist(#CSV)
)
UPDATE PT
SET MaxAllowance = #MaxAllowance,
AllowanceType = #AllowanceType,
AllowancePeriod = #AllowancePeriod
FROM dbo.ProdTerm AS PT
INNER JOIN Test AS T ON PT.Product_ID = T.Value;