Inside Microsoft® SQL Server™ 2005

Dealing with Each Row Individually

Remember that cursors can be useful when the problem is a procedural one, and you must deal with each row individually. I provided examples of such scenarios earlier. Here I want to show an alternative to cursors that programmers may use to apply iterative logic, and compare its performance with the cursor code I just demonstrated in the previous section. Remember that the cursor code that scanned a million rows took approximately 20 seconds to complete. Another common technique to iterate through a table’s rows is to loop through the keys and use a set-based query for each row. To test the performance of such a solution, make sure the Discard Results After Execution option in SSMS is still turned on. Then run ...