Populate rows based on another row ( Copy Prices from branch 0, to all other branches) - sql

Question

I am trying to populate rows based on another row,
For example
Update the Product Price table where branchID = 0
to all other products where the branchid <> 0 based on each product code
In the table there is
7 rows of the same product, each row is meant to be identical, but the only difference is the branchid
I want all data from branch 0 row to populate the rest for the product
my current update script does run, but it uses up so much space on the transaction log that it fails, and it takes 2 hours to run
UPDATE ProductPrice
SET StandardSell = pp2.StandardSell,
StandardBuy = pp2.StandardBuy,
InternalCost = pp2.InternalCost,
BuyPerID = pp2.BuyPerID,
AverageCostPerID = pp2.AverageCostPerID,
InternalCostPerID = pp2.InternalCostPerID,
SellPerID = pp2.SellPerID
FROM (SELECT BranchID, ProductID, StandardSell, StandardBuy,SellPerID, InternalCost,BuyPerID,AverageCostPerID,InternalCostPerID
FROM ProductPrice
WHERE BranchID = 0
) AS pp2 INNER JOIN
ProductPrice AS pp1
on pp1.ProductID = pp2.ProductID
WHERE pp1.ProductID = pp2.ProductID
I want products to be updated with the prices from branch 0 to all other branches per product.

Answer 1

This is too long for a comment.
The first observation is that you should fix your data model. Repeating the same columns on seven records is evidence that your data is not normalized. The seven columns that you want to update should probably be in the ProductPrice table.
Then you want a ProductBranch table, with additional columns and the branch id.
That said, if you are stuck with the data model, you are stuck with an update that basically updates all rows. Instead, create a new table with all the columns you want:
insert into temp_productprice
select . . .
from . . .;
Then truncate productprice and insert the new data into it. A bulk insert is more efficient than a giant update.
Finally, you could also try using window functions:
with toupdate as (
select pp.*,
max(case when branchid = 0 then StandardSell end) as StandardSell_0,
max(case when branchid = 0 then StandardBuy end) as StandardBuy_0,
from productprice pp
. . .
)
update toupdate
set StandardSell = StandardSell_0,
StandardBuy = StandardBuy_0,
. . .
from branchid <> 0;

Answer 2

Thank you for your suggestions,
In the end I just gave the log file more space. Then let it run- it takes 2 hours though lol.
But its done
Thanks the script i posted works for anyone elses use.