There is actually another way to archive a row by row processing. I am using it in different scenarios since quite a few years and it turned out to be very efficient.

BEGIN

Declare @ID int

Select @ID = Min(ID) from emp

WHILE @ID Is Not Null

BEGIN

UPDATE emp SET salary = (salary * 115) /100 WHERE emp.id = @ID

Select @ID = Min(ID) from emp where ID > @ID

END

END

In relation to the actual performance of this method I listed the times/cost on my server below. Please note that I also included the cost calculated by the execution plan:

READESTIMATED EXECUTION COST

Direct SQL50.0132935 100%

Cursor690.14620601099%

Temp table with TOP2540.25310071904%

Temp table with IDENTITY column1210.0994881 748%

Min Loop390.0861955 648%

🙂