We heard count(1) is faster then count(*). Lets do a workshop on this .
Above is Copy_customer table where inserted both null and not null values.
lets execute the queries Count(*) and count(1) and verify the result and verify the work load.
In both cases query will return the same output. Now lets compare the work load of both the queries.
Let's check for count(*)
Now Count(1)
From the above screen shot its clearly shows both queries are taking same amount of work load to execute.
Now lets verify the same query output and work load with actual column name instead of '1' and '*'.
Now if check the below output it will ignore the null from the result and trace file also using the index.
Here Elapsed time is little more to count(1) and count(*). Because here it also fetches more then 90% record. This article is only to demonstrate count(1) and count(*) are same.
Thank you....for eading