I have a temp table with the following structure which gets populated with around 20k row of data (from another join query and populated in advance)

tempTable:

Now, I want to be able to use the above data to update another table which has the following scheama.

masterTable:

So that, order_id 123 of the masterTable will be updated with 456.

I also want to be able to roll back the update if needed later.

For this, I can think of two approaches.

1. a simple update, like below

   update 
      masterTable
   set
      order_id = t.order_id
   from
      masterTable as m
   join
      @tempTable as t
   on
      m.process_id = t.process_id
   

2. write a Stored Procedure, which will loop over every row in the tempTable and update the masterTable.

   CREATE PROCEDURE UpdateMasterTableProcessID
   AS
   BEGIN
       -- Declare variables to hold the values from the tempTable
       DECLARE @order_id INT;
       DECLARE @process_id INT;
   
       -- Declare a cursor for iterating over the tempTable
       DECLARE cur CURSOR FOR
       SELECT order_id, process_id
       FROM tempTable;
   
       -- Open the cursor
       OPEN cur;
   
       -- Fetch the first row from the cursor
       FETCH NEXT FROM cur INTO @order_id, @process_id;
   
       -- Loop through the result set
       WHILE @@FETCH_STATUS = 0
       BEGIN
           -- Update the masterTable for the current row
           UPDATE masterTable
           SET process_id = @process_id
           WHERE order_id = @order_id;
   
           -- Fetch the next row from the cursor
           FETCH NEXT FROM cur INTO @order_id, @process_id;
       END;
   
       -- Close and deallocate the cursor
       CLOSE cur;
       DEALLOCATE cur;
   END;
   

Can somebidy tell me what would be the better approach between these two pls?

I think SP may be better as I can then add new columns called Updated and keep it updated, so that I know which record has been updated and which isn’t. but I want to evaluate the pros and cons of each approach given I would be updating around 20k records.