Need to prove an application is killing my SQL Server!

Hi

I was forces to open many VIEWS to an external department on my SQL Server. Unfortunately I was not allowed to limit these VIEWS and some of them are huge.

The reason I did this was another Department need read access on some data which then goes into an application. I said that I was concerned that this may kill my DB if badly written queries were used but I was told to back-off….

Well, my CPU on my SQL Box is now at 80% and the management said I need to prove that it is the other persons link which is doing it. Any ideas how to do that? Never really used perfmon for real, just read up on it for exams!

Rich