How to tune a T-SQL with Query Cost 100%?
This is indeed an interesting question and I have received during Comprehensive Database Performance Health Check.
How to tune a T-SQL with Query Cost 100%?
This is indeed an interesting question and I have received during Comprehensive Database Performance Health Check.
One of the most popular questions I received during my Comprehensive Database Performance Health Check is Finding Queries Using Particular Index.
Today we will take the same conversation to the next level by discussing Single Scan for 3 Operations – COUNT(*) COUNT(1) SUM(1).
One question that kept on coming up was SUM(1) vs COUNT(*) – Performance Observation. Well, let us see that today.
Today we are building a Collection of Articles that have recently generated interest on the blog as well as on the YouTube channel – SQL in Sixty Seconds.
DBA suspects those operations are using lots of clustered index scans. Let us discuss today COUNT(*) and Index Used. Let’s learn.
Are Index Scans Bad? The answer No. Index Scans are Not Always Bad. This was in-depth discussed with my client during the Health Check.